Story highlights Obama says he hopes a truce will give space to reach a political solution

He pushes for a unity government to pave the way for fair and free elections

Ukrainians should be able to "determine their own destiny," Obama adds

U.S. puts Ukrainians responsible for crackdown on visa ban list

The United States talked tough Wednesday about trying to halt escalating political violence in Ukraine, but analysts warned there was little that outside pressure could do, especially if the Ukrainian military gets involved on the side of the government cracking down on protesters.

President Barack Obama condemned the unrest that killed 26 people on Tuesday and began spreading Wednesday beyond Kiev, the Ukrainian capital, with reports of protesters taking over government buildings in the nation's western region.

Obama said the United States expected the Ukrainian government to show restraint against peaceful protesters, and he warned there would be unspecified consequences for excessive action. He made a point of saying the Ukrainian military should stay out of it, as it has so far.

Later in the day -- after Ukraine's president and opposition leaders agreed to a truce and to fresh talks -- Obama said he hoped this development will "provide space for the sides to resolve their disagreements peacefully."

Insisting that Ukraine isn't a pawn on some "Cold War chessboard" with Russia, Obama said that he hopes a unity government will be formed to pave the way for "fair and free elections."

"The situation that happened in Ukraine has to do with whether or not the people ... can determine their own destiny," he said.

Photos: Photos: Ukraine protests turn deadly Photos: Photos: Ukraine protests turn deadly Ukraine protests turn deadly – Protesters in Kiev, Ukraine, clash with police in Independence Square on Wednesday, February 19. Thousands of anti-government demonstrators have packed the square since November, when President Viktor Yanukovych reversed a decision on a trade deal with the European Union and instead turned toward Russia. Hide Caption 1 of 88 Photos: Photos: Ukraine protests turn deadly Ukraine protests turn deadly – Protesters clash with police in Kiev on February 19. The unrest in Ukraine intensified after an anti-protest law went into effect in January. Demonstrators took to the streets to protest the law, which was later repealed. Hide Caption 2 of 88 Photos: Photos: Ukraine protests turn deadly Ukraine protests turn deadly – Protesters prepare a barricade in Independence Square on February 19. Hide Caption 3 of 88 Photos: Photos: Ukraine protests turn deadly Ukraine protests turn deadly – Police form a line as the Trade Unions Building burns in Independence Square on February 19. Hide Caption 4 of 88 Photos: Photos: Ukraine protests turn deadly Ukraine protests turn deadly – Police form a barrier in Independence Square on February 19. Hide Caption 5 of 88 Photos: Photos: Ukraine protests turn deadly Ukraine protests turn deadly – Protesters in Kiev throw rocks at riot police in Independence Square on February 19. Hide Caption 6 of 88 Photos: Photos: Ukraine protests turn deadly Ukraine protests turn deadly – Independence Square smolders during protests on February 19. Hide Caption 7 of 88 Photos: Photos: Ukraine protests turn deadly Ukraine protests turn deadly – Protesters walk in the rubble of Independence Square on February 19. Hide Caption 8 of 88 Photos: Photos: Ukraine protests turn deadly Ukraine protests turn deadly – Protesters gather in Kiev on February 19. Hide Caption 9 of 88 Photos: Photos: Ukraine protests turn deadly Ukraine protests turn deadly – A protester throws a cobblestone at riot police during clashes in Independence Square on February 19. Hide Caption 10 of 88 Photos: Photos: Ukraine protests turn deadly Ukraine protests turn deadly – Riot police officers rest against a column in Independence Square on February 19. Hide Caption 11 of 88 Photos: Photos: Ukraine protests turn deadly Ukraine protests turn deadly – Protesters stand in Independence Square on February 19. Hide Caption 12 of 88 Photos: Photos: Ukraine protests turn deadly Ukraine protests turn deadly – An injured protester is moved out during clashes with riot police in Kiev on February 19. Hide Caption 13 of 88 Photos: Photos: Ukraine protests turn deadly Ukraine protests turn deadly – A protester uses a slingshot to throw a rock at riot police February 19 in Kiev. Hide Caption 14 of 88 Photos: Photos: Ukraine protests turn deadly Ukraine protests turn deadly – Riot police line up in Kiev on February 19. Hide Caption 15 of 88 Photos: Photos: Ukraine protests turn deadly Ukraine protests turn deadly – Protesters put on gas masks near the perimeter of Independence Square on February 19. Hide Caption 16 of 88 Photos: Photos: Ukraine protests turn deadly Ukraine protests turn deadly – Protesters brace themselves for more violence in Kiev on February 19. Hide Caption 17 of 88 Photos: Photos: Ukraine protests turn deadly Ukraine protests turn deadly – A protester throws a stone in Kiev on February 19. Hide Caption 18 of 88 Photos: Photos: Ukraine protests turn deadly Ukraine protests turn deadly – Protesters protect themselves with shields as they clash with police in Kiev on February 19. Hide Caption 19 of 88 Photos: Photos: Ukraine protests turn deadly Ukraine protests turn deadly – An injured protester waits to be treated in a Kiev monastery, converted into a makeshift hospital, on February 19. Hide Caption 20 of 88 Photos: Photos: Ukraine protests turn deadly Ukraine protests turn deadly – Protesters sleep on the floor inside a Kiev monastery on February 19. Hide Caption 21 of 88 Photos: Photos: Ukraine protests turn deadly Ukraine protests turn deadly – Protesters clash with police in Independence Square on February 19. Hide Caption 22 of 88 Photos: Photos: Ukraine protests turn deadly Ukraine protests turn deadly – A protester rushes through a broken door in the regional prosecutor's office in Lviv, Ukraine, on February 19. Police said the unrest has spread to western Ukraine, with protesters attacking police and local government offices in a number of regions. Hide Caption 23 of 88 Photos: Photos: Ukraine protests turn deadly Ukraine protests turn deadly – Protesters in Lviv burn papers from a government building on February 19. Hide Caption 24 of 88 Photos: Photos: Ukraine protests turn deadly Ukraine protests turn deadly – A protester aims a weapon in Kiev on Tuesday, February 18. Hide Caption 25 of 88 Photos: Photos: Ukraine protests turn deadly Ukraine protests turn deadly – Riot police storm Independence Square on February 18. Hide Caption 26 of 88 Photos: Photos: Ukraine protests turn deadly Ukraine protests turn deadly – A protester runs during clashes with police in Kiev on February 18. Hide Caption 27 of 88 Photos: Photos: Ukraine protests turn deadly Ukraine protests turn deadly – Protesters clash with police in Independence Square on February 18. Hide Caption 28 of 88 Photos: Photos: Ukraine protests turn deadly Ukraine protests turn deadly – Protesters watch clashes in Kiev on February 18. Hide Caption 29 of 88 Photos: Photos: Ukraine protests turn deadly Ukraine protests turn deadly – Violence between police and protesters escalates February 18 in Kiev. Hide Caption 30 of 88 Photos: Photos: Ukraine protests turn deadly Ukraine protests turn deadly – Riot police stand firm in Kiev on February 18. Hide Caption 31 of 88 Photos: Photos: Ukraine protests turn deadly Ukraine protests turn deadly – Protesters burn a car in central Kiev on February 18. Hide Caption 32 of 88 Photos: Photos: Ukraine protests turn deadly Ukraine protests turn deadly – A protester stands atop a barricade in Kiev on February 18. Hide Caption 33 of 88 Photos: Photos: Ukraine protests turn deadly Ukraine protests turn deadly – Protesters clash with riot police outside Ukraine's parliament in Kiev on February 18. Hide Caption 34 of 88 Photos: Photos: Ukraine protests turn deadly Ukraine protests turn deadly – A rainbow forms over a protester ducking for cover in Kiev on February 18. Hide Caption 35 of 88 Photos: Photos: Ukraine protests turn deadly Ukraine protests turn deadly – Riot police protect themselves during clashes in Kiev on February 18. Hide Caption 36 of 88 Photos: Photos: Ukraine protests turn deadly Hide Caption 37 of 88 Photos: Photos: Ukraine protests turn deadly Ukraine protests turn deadly – A protester is engulfed in flames while running from the clashes in Kiev on February 18. Hide Caption 38 of 88 Photos: Photos: Ukraine protests turn deadly Ukraine protests turn deadly – Riot police detain a protester in Kiev on February 18. Hide Caption 39 of 88 Photos: Photos: Ukraine protests turn deadly Ukraine protests turn deadly – Protesters invade the main office of the ruling Party of Regions in Kiev on February 18. Hide Caption 40 of 88 Photos: Photos: Ukraine protests turn deadly Ukraine protests turn deadly – Riot police shield themselves during clashes with protesters on February 18. Hide Caption 41 of 88 Photos: Photos: Ukraine protests turn deadly Ukraine protests turn deadly – Protesters throw stones toward riot police in Kiev on February 18. Hide Caption 42 of 88 Photos: Photos: Ukraine protests turn deadly Ukraine protests turn deadly – A protester holds a Ukrainian flag in Independence Square on Tuesday, February 4. Hide Caption 43 of 88 Photos: Photos: Ukraine protests turn deadly Ukraine protests turn deadly – A protester smokes a cigarette while standing guard in Kiev on February 4. Hide Caption 44 of 88 Photos: Photos: Ukraine protests turn deadly Ukraine protests turn deadly – Protesters keep an eye on police February 4 as they man a barricade in Kiev. Hide Caption 45 of 88 Photos: Photos: Ukraine protests turn deadly Ukraine protests turn deadly – A protester is reflected in a broken mirror during protests in Kiev on Monday, February 3. Hide Caption 46 of 88 Photos: Photos: Ukraine protests turn deadly Ukraine protests turn deadly – Opposition supporters warm themselves in Kiev on Saturday, February 1. Hide Caption 47 of 88 Photos: Photos: Ukraine protests turn deadly Ukraine protests turn deadly – A protester stands on top of barricades in Kiev on Tuesday, January 28. Hide Caption 48 of 88 Photos: Photos: Ukraine protests turn deadly Ukraine protests turn deadly – Protesters sit behind a barricade in Kiev on January 28. Hide Caption 49 of 88 Photos: Photos: Ukraine protests turn deadly Ukraine protests turn deadly – Protesters march in Kiev on Monday, January 27. Activists say they want wide-ranging constitutional reform and a shake-up of the Ukrainian political system. Hide Caption 50 of 88 Photos: Photos: Ukraine protests turn deadly Ukraine protests turn deadly – Police block a street in Kiev on January 27. Hide Caption 51 of 88 Photos: Photos: Ukraine protests turn deadly Ukraine protests turn deadly – A couple try to keep warm near a fire at a barricade in Kiev on January 27. Hide Caption 52 of 88 Photos: Photos: Ukraine protests turn deadly Ukraine protests turn deadly – Riot police block a Kiev street from protesters on January 27. Hide Caption 53 of 88 Photos: Photos: Ukraine protests turn deadly Ukraine protests turn deadly – Protesters stand guard inside the Ukraine Justice Ministry in Kiev on January 27. Demonstrators later left the building because they didn't want to create any difficulties in negotiations between the government and opposition, a protest leader said. Protesters repositioned themselves outside and blocked access to the building, the leader said. Hide Caption 54 of 88 Photos: Photos: Ukraine protests turn deadly Ukraine protests turn deadly – Orthodox priests lead the funeral service for slain protester Mikhail Zhiznevsky in Kiev on Sunday, January 26. Hide Caption 55 of 88 Photos: Photos: Ukraine protests turn deadly Ukraine protests turn deadly – Riot police officers stand in line during anti-government protests in Kiev on Saturday, January 25. Hide Caption 56 of 88 Photos: Photos: Ukraine protests turn deadly Ukraine protests turn deadly – An Orthodox priest prays during protests on January 25. Hide Caption 57 of 88 Photos: Photos: Ukraine protests turn deadly Ukraine protests turn deadly – Some 10,000 Ukrainians take part in the funeral ceremony of dead protester Yuri Verbytsky in the western city of Lviv on Friday, January 24. Hide Caption 58 of 88 Photos: Photos: Ukraine protests turn deadly Ukraine protests turn deadly – A line of Ukrainian riot police block a road on January 24. Hide Caption 59 of 88 Photos: Photos: Ukraine protests turn deadly Ukraine protests turn deadly – A protester puts on a gas mask near Dynamo Stadium in Kiev on January 24. Hide Caption 60 of 88 Photos: Photos: Ukraine protests turn deadly Photos: Ukraine protests turn deadly – Ukrainian Oksana Tikhomirova cries as she urges riot police to stop the violence outside a government district in central Kiev on January 24. Hide Caption 61 of 88 Photos: Photos: Ukraine protests turn deadly Ukraine protests turn deadly – Molotov cocktails sit in a basket ready to be used by protesters in Kiev on January 24. Hide Caption 62 of 88 Photos: Photos: Ukraine protests turn deadly Ukraine protests turn deadly – Riot police stand guard near Dynamo Stadium on January 24. Hide Caption 63 of 88 Photos: Photos: Ukraine protests turn deadly Ukraine protests turn deadly – A protester passes past graffiti that reads "Government for People" in the Ministry of Agricultural Policy building in Kiev on January 24. Hide Caption 64 of 88 Photos: Photos: Ukraine protests turn deadly Ukraine protests turn deadly – A man walks past the wreckage of a car on January 24. Hide Caption 65 of 88 Photos: Photos: Ukraine protests turn deadly Ukraine protests turn deadly – Ukrainian protesters use a huge catapult to throw stones at riot police as tires burn in Kiev on Thursday, January 23. Hide Caption 66 of 88 Photos: Photos: Ukraine protests turn deadly Ukraine protests turn deadly – Riot police officers gather in Kiev on January 23. Hide Caption 67 of 88 Photos: Photos: Ukraine protests turn deadly Ukraine protests turn deadly – Opposition leader Vitali Klitschko, center, addresses protesters near the burning barricades between police and protesters in central Kiev on January 23. Hide Caption 68 of 88 Photos: Photos: Ukraine protests turn deadly Ukraine protests turn deadly – Riot police stand guard near a burnt-out bus covered in icicles in Kiev on January 23. Hide Caption 69 of 88 Photos: Photos: Ukraine protests turn deadly Ukraine protests turn deadly – A protester walks past burning tires in Kiev on January 23. Hide Caption 70 of 88 Photos: Photos: Ukraine protests turn deadly Ukraine protests turn deadly – A protester shoots fireworks at police during clashes in Kiev on January 23. Hide Caption 71 of 88 Photos: Photos: Ukraine protests turn deadly Ukraine protests turn deadly – A protester carries tires toward a fire on January 23. Hide Caption 72 of 88 Photos: Photos: Ukraine protests turn deadly Ukraine protests turn deadly – Riot police officers line up in Kiev during clashes on Wednesday, January 22. Hide Caption 73 of 88 Photos: Photos: Ukraine protests turn deadly Ukraine protests turn deadly – A protester throws a Molotov cocktail on January 22. Hide Caption 74 of 88 Photos: Photos: Ukraine protests turn deadly Ukraine protests turn deadly – Protesters shoot from behind a shield among burning automobile tires in Kiev on January 22. Hide Caption 75 of 88 Photos: Photos: Ukraine protests turn deadly Ukraine protests turn deadly – Riot police officers gather as they clash with protesters in the center of Kiev on January 22. Hide Caption 76 of 88 Photos: Photos: Ukraine protests turn deadly Ukraine protests turn deadly – A protester throws a Molotov cocktail during clashes with police in central Kiev. Hide Caption 77 of 88 Photos: Photos: Ukraine protests turn deadly Ukraine protests turn deadly – Ukrainian protesters are seem during a mass action of opposition on Grushevsky Street. Hide Caption 78 of 88 Photos: Photos: Ukraine protests turn deadly Ukraine protests turn deadly – A protester throws a stone in front of a plume of fire and smoke during clashes with police in central Kiev. Hide Caption 79 of 88 Photos: Photos: Ukraine protests turn deadly Ukraine protests turn deadly – Flames leap off a protester during clashes with police on January 22. Hide Caption 80 of 88 Photos: Photos: Ukraine protests turn deadly Ukraine protests turn deadly – A police officer aims his shotgun during clashes with protesters. Hide Caption 81 of 88 Photos: Photos: Ukraine protests turn deadly Ukraine protests turn deadly – Paramedics put a wounded man on a stretcher and into a medical vehicle. Hide Caption 82 of 88 Photos: Photos: Ukraine protests turn deadly Ukraine protests turn deadly – Ukrainian police storm protesters' barricades in Kiev amid violent clashes on January 22. Hide Caption 83 of 88 Photos: Photos: Ukraine protests turn deadly Ukraine protests turn deadly – A European integration supporter is seen in Independence Square. Hide Caption 84 of 88 Photos: Photos: Ukraine protests turn deadly Ukraine protests turn deadly – Protesters are seen in front of burning tires on Grushevsky Street. Hide Caption 85 of 88 Photos: Photos: Ukraine protests turn deadly Ukraine protests turn deadly – A medic treats an injured protester's leg during violent clashes between demonstrators and police. Hide Caption 86 of 88 Photos: Photos: Ukraine protests turn deadly Ukraine protests turn deadly – A Ukrainian man stands in front of riot police on January 22. Hide Caption 87 of 88 Photos: Photos: Ukraine protests turn deadly Ukraine protests turn deadly – Protesters clash with police in Kiev as snow falls on January 22. Hide Caption 88 of 88

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Visa ban

Later, the United States issued a visa ban for 20 senior members of the Ukrainian government and others responsible for the violent crackdown in Kiev, a senior State Department official told reporters on a conference call.

However, Council on Foreign Relations President Richard Haass told CNN that the United States and its European allies have limited options for impacting the situation on the ground in Ukraine.

"My own hunch is this is going to continue to escalate," Haass said, adding that the main question was whether the military would side with the government by getting involved or back the protesters by remaining in barracks.

In what the senior State Department official called "a glimmer of hope," the Ukrainian government and the opposition announced a truce Wednesday night to allow for negotiations to restart with the aim at stabilizing the situation.

Earlier, Obama said while attending talks in Mexico with the leaders of Canada and the host country that "we're going to be watching closely and we expect the Ukrainian government to show restraint, to not resort to violence in dealing with peaceful protesters."

Ukraine's military a focus

Thousands of demonstrators have packed Independence Square in Kiev since November, when President Viktor Yanukovych reversed a decision to sign a trade deal with the European Union and instead turned toward Russia.

The unrest intensified after an anti-protest law went into effect. On Tuesday, the street clashes escalated dramatically, leaving 26 people dead and buildings on fire.

Vice President Joe Biden spoke to Yanukovych on Tuesday night to express "grave concern" over the crisis.

A readout of the conversation released by the White House said Biden told the Ukrainian leader that "the United States condemns violence by any side, but that the government bears special responsibility to de-escalate the situation."

Secretary of State John Kerry reiterated Biden's message on Wednesday, saying Yanukovych can choose either dialogue and compromise or violence and mayhem.

"It is in his hands to decide what the future of the Ukraine and the future hopes of his people will be, and we hope very much that violence will be avoided and compromise will be found," Kerry said.

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Wednesday night, Ukraine military forces moved into defensive positions around military bases and weapons depots across the country, according to a U.S. defense official familiar with the latest intelligence.

The move was considered as defensive to secure facilities and weapons, and so far only involved military personnel rather than any widespread movement of armored vehicles, according to the defense official who spoke on condition of not being identified.

"We are encouraged the Ukraine military has not been brought into this crisis and we urge them to remain on the sidelines," said Pentagon spokesman Col. Steve Warren.

If the Ukraine military got involved in the fighting, "that would have consequences for our defense relationship," Warren added.

Ukraine cites terrorists for trouble

While Yanukovych's government has received most of the blame, Ukrainian officials blamed protesters for the escalating unrest.

Security chief Oleksander Yakimenko accused protesters of looting weapons and ammunition from government offices and announced a nationwide "anti-terrorist operation."

According to senior U.S. administration officials, such language by Ukraine signals a hardening government position against the protesters.

In a later conference call with reporters, the senior State Department official -- who spoke on condition of not being identified -- expressed concern over the replacement of Ukraine's military armed forces chief. No reason was given for the dismissal of Col. Gen. Volodymyr Zamana.

Russia, which has major historical and economic ties to the former Soviet territory, accuses the United States of playing a role in the widespread protests. The senior State Department official denied that on Wednesday, saying "we completely reject their notion that we have been interfering."

The visa bans announced Wednesday followed an earlier move in January when existing visas of some Ukrainians were revoked over previous unrest, the State Department official said.

This time, the 20 Ukrainians -- none of them from the military -- now banned from getting new U.S. visas "represent the full chain of command that we consider responsible for ordering security forces to move against" protesters on Tuesday, the official added.

Sanctions talk

Other sanctions in coordination with the European Union also could occur, according to the official, who declined to provide further details.

France also has threatened sanctions against Ukraine over the government's crackdown, with President Francois Hollande calling the protest violence "unspeakable, unacceptable, intolerable acts."

The Obama administration has come under increasing criticism for its foreign policy as talks have faltered on halting Syria's civil war, which left nearly 5,000 people dead in the last three weeks in a particularly violent stretch of the almost three-year conflict.

On Sunday, veteran GOP Sen. John McCain of Arizona called the U.S. policy in Syria an "abysmal failure and a disgraceful one."