The European Union agreed this evening to impose sanctions on those responsible for deadly violence in Ukraine and warned it would ratchet up the pressure if the situation there got worse.

As Ukraine suffered its bloodiest day since Soviet times, EU foreign ministers meeting in emergency session in Brussels decided on measures against Kiev including visa bans, asset freezes and a suspension of the export of riot control equipment like water cannon, body armour and helmets.

Although the EU cited no names, officials said those targeted for sanctions may include ministers but not President Viktor Yanukovich himself, at least for now. Protest leaders found responsible for violence could also go on the sanctions list.

At the same time, the EU pushed on with its attempt to broker a peaceful solution to a conflict that has left dozens dead, including up to 60 people today.

The foreign ministers of Germany, France and Poland did not attend the Brussels meeting, as planned, after deciding to stay on in the Ukrainian capital Kiev to continue contacts with the government and opposition.

"I think (ministers) were truly alarmed, shocked by the scale of violence that has taken place, and that will drive the agenda as it drove the agenda today," EU foreign policy chief Catherine Ashton said.

"The work of the three ministers is crucial on the ground and we will be in constant touch with them to seek their advice and to see what efforts they are able to make, what progress they're able to make," she told a news conference.

The EU decided "as a matter of urgency to introduce targeted sanctions" against people responsible for human rights violations, violence and use of excessive force in Ukraine, the foreign ministers said in a statement.

"The scale of implementation will be taken forward in the light of developments in Ukraine," they said.

The EU will start work immediately on drawing up an initial list of people affected by sanctions but it could be several days before it is published, officials said.

Speaking after the foreign affairs meeting, Tánaiste Eamon Gilmore said he expected the list of individuals to whom the restrictions will apply, to be agreed by the end of the week.

“The decision was made unanimously. We are targeting specifically people who are responsible for the violence,” the Tánaiste said.

“The intention is that the scale of those sancctions will be applied on a progressve basis as the situation develops in Ukraine.”

Minister Gilmore said ministers were regularly updated by the French, German and Polish foreign ministers during the course of the meeting, who held a six hour meeting with President Victor Yanukovich in Kiev, as well as meeting opposition leaders.

“What we want to achieve is an end of the violence, what we want to achieve is political progress in Ukraine. The decisions today show a clear determination by the European Union, unanimously, to try and move things forward.”

Speaking as she left the Brussels meeting this afternoon, Italian Foreign Minister Emma Bonino said “The decision is to proceed very rapidly, in the next hours, to a visa ban and asset freeze on those who have committed the violence.

Ministers called for an immediate end to the violence, full respect for human rights and urgent independent investigations into human rights violations.

The United States yesterday imposed visa bans on 20 senior Ukrainian government officials believed to be responsible for the violence against protesters, but it did not give their names.

Just three months ago, EU officials had hoped Ukraine would sign a far-reaching trade and cooperation deal with Brussels, provided certain conditions were met. Those included the release of jailed opposition leader Yulia Tymoshenko.

The death toll is mounting in Ukraine as a new wave of deadly clashes in the capital today has destroyed a truce declared last night by President Viktor Yanukovych and opposition leaders.

While the Health Ministry reported seven dead, including two policemen, one doctor was quoted by the AFP news agency as saying that 60 people had died.

Agence France Presse said at least 25 people were killed, citing two reporters at the scene. The Kyiv Post said as many as 35 people died.

The country’s interior ministry said protesters are holding 67 policemen hostage in the capital.

Earlier the ministry said “Berkut“ riot policemen had been armed with combat weapons, an attempt to regain control of violent protests in which at least 50 people have died since Tuesday.

“To free the hostages police have the right to use their weapons,“ the ministry said in a statement posted to its website.

A further three policemen were unaccounted for, it said.

Violent skirmishes broke out after 8am this morning on Independence Square, the hub of the demonstrations.

The capital’s mayor resigned from Mr Yanukovych’s party and reopened the subway, while ruling-party deputies urged parliament to convene.

Russian President Vladimir Putin is sending an envoy to the country at the request of president Yanukovich, to try to mediate talks between the government and opposition, the Kremlin said today.

Russia had until now avoided involvement in any efforts to mediate between Mr Yanukovich and his foes in an escalating dispute that began when the Ukrainian leader scrapped plans for deals with the EU in favour of closer ties with Moscow.

Mr Yanukovich telephoned Mr Putin and asked him “to send a Russian representative to Kiev to participate as a mediator in the negotiations process with the opposition”, the Kremlin said in a statement. “Vladimir Putin decided to send human rights ombudsman Vladimir Lukin on this mission,” it said.

A sniper killed protesters on the square, the Ukrainska Pravda newspaper reported. The Interior Ministry accused a sniper in the tent camp of wounding 20 police offices with gunfire.

A Reuters photographer counted 21 bodies in civilian clothes in three places on the square, a few hundred yards from the presidency. That raised the death toll since Tuesday to at least 43, by far the bloodiest hours of Ukraine’s 22-year post-Soviet history.

Demonstrators hurling rocks and petrol bombs charged riot police ranks near Independence Square, forcing them to retreat towards parliament and government headquarters, as activists reclaimed much of the territory they lost during deadly street battles on Tuesday.

Police claimed today that they had been fired upon with live rounds and protesters said they had caught a police sniper.

Neither claim could be confirmed.

Injured protesters were carried on stretchers, doors and in blankets through Independence Square to waiting ambulances and other vehicles, and demonstrators surrounded captured police officers and marched them through the square.

“We don’t beat the prisoners! Stay calm. Be reasonable. Get medical staff to the prisoners, clear a path for the prisoners,” a speaker called from the stage on the square. He also urged people to rebuild barricades and appealed for blood donors.

Mr Yanukovich’s website this morning announced an accord for “the start to negotiations with the aim of ending bloodshed, and stabilising the situation in the state in the interest of social peace.”

Mr Yanukovich had denounced the bloodshed in central Kiev, where protesters have been dug in for almost three months since he spurned a trade deal with the European Union in favor of closer Russian ties, as an attempted coup.

Additional reporting: Reuters