Washington (CNN) Vice President Joe Biden ratcheted up US rhetoric on Moscow Wednesday night, for the first time calling Russian President Vladimir Putin a 'dictator.'

The undiplomatic description comes as American authorities finger his government for a hacking incident allegedly seeking to influence the US presidential elections in yet another intensification of tensions between the historic adversaries.

"We cannot elect a man who belittles our closest allies while embracing dictators like Vladimir Putin," said Biden, "a man who confuses bluster with strength. We simply cannot let that happen as Americans. Period."

Biden's comments about Putin come amid controversy over Democratic National Committee emails damaging to Democratic nominee Hillary Clinton, which the US intelligence community believe were most likely hacked by Russia and then posted on the WikiLeaks site.

Biden's remark, made in the context of a political speech, drew applause from a sympathetic audience of Democratic delegates frustrated with Trump's seemingly warm views toward Putin and Russia.

But in using the term, he risks further fraying the already strained relationship between the Obama and Putin governments at a time when they are mired in a series of global crisis where their separate and mutual interests are at stake.

In calling the Russian president a "dictator," Biden is echoing criticism lobbed at the leader by his domestic political opponents, who say Putin is tightening his grip on power through increasingly authoritarian tactics.

It's a term rarely invoked by the Obama administration, and typically reserved for American's staunchest geopolitical foes, such as North Korea's Kim Jong Un and Syria's Bashar al-Assad. At previous, less overtly political moments, the White House has dismissed the suggestion that the countries are returning to their traditional antagonistic roles and rejected assessments -- sometimes from senior military officers -- that Russia poses the largest threat to America.

A White House official said Thursday morning that Biden's description of Putin didn't reflect an official administration stance, though no official designation for "dictator" exists in legal or diplomatic proceedings.

But White House spokesman Josh Earnest noted later Thursday that a State Department report described Russia as having "a highly centralized, authoritarian political system, dominated by President Vladimir Putin."

Earnest continued, "You'd be hard-pressed to draw a distinction between the word that Vice President Biden used and the language that was included in the State Department."

He wouldn't say, however, whether President Barack Obama believes Putin is a dictator.

In applying the term to Putin, Biden is disparaging the leader of a country that, while often at odds with the US, has also been a key partner on issues like Iran's denuclearization and the fight against ISIS in Syria.

Photos: Tense moments between Obama and Putin Photos: Tense moments between Obama and Putin Barack Obama and Russian President Valdimir Putin toast during a luncheon hosted by United Nations Secretary-General Ban Ki-moon during the 70th annual U.N. General Assembly on September 28 in New York City. Hide Caption 1 of 7 Photos: Tense moments between Obama and Putin Obama and Putin shake hands while posing for a photo ahead of their meeting at U.N. headquarters on September 28 in New York. Hide Caption 2 of 7 Photos: Tense moments between Obama and Putin Putin speaks with Obama during the Asia-Pacific Economic Cooperation summit in Beijing, China on November 11, 2014. U.S.-Russia relations have descended to a new low since Russia annexed Crimea in March. Hide Caption 3 of 7 Photos: Tense moments between Obama and Putin Obama and Putin share a comical and awkward moment on a large split-screen during an international ceremony on the stretch code-named Sword Beach, in Ouistreham, France, to commemorate the Allied invasion of Normandy on June 6, 2014. Obama and Putin had an informal 15-minute chat during lunch at the ceremony that marked the 70th anniversary of the D-day landings. "It's a positive thing that they spoke, but more needs to be done," a senior U.S. official said at the time. Hide Caption 4 of 7 Photos: Tense moments between Obama and Putin Putin greets Obama at the G-20 summit on September 5, 2013 in St. Petersburg, Russia. The United States and Russia have been squaring off over the bloody civil war in Syria. Hide Caption 5 of 7 Photos: Tense moments between Obama and Putin Obama listens to Putin after their bilateral meeting in Los Cabos, Mexico on June 18, 2012 on the sidelines of the G-20 summit. The meeting was the first time Obama and Putin held face-to-face talks since Putin returned to the president's office earlier that year. Obama said he and Putin discussed the conflict in Syria and "agreed that we need to see a cessation of the violence, that a political process has to be created to prevent civil war." Hide Caption 6 of 7 Photos: Tense moments between Obama and Putin Obama, who had become U.S. President six months earlier, enjoys tea with then-Prime Minister Vladimir Putin and members of the American delegation at Putin's dacha on July 7, 2009 in Moscow. Hide Caption 7 of 7

Until now, it's a line the White House has not crossed with respect to Putin.

Obama has been asked several times in interviews and news conferences to give his take on Putin but has preferred to critique his counterpart's policies and actions as opposed to making broader assessments of his leadership style.

At a G7 summit last year, Obama offered perhaps his most pointed criticism of Putin, saying the leader has a choice to make: "Does he continue to wreck his country's economy and continue Russia's isolation in pursuit of a wrong-headed desire to recreate the glories of the Soviet Empire? Or does he recognize that Russia's greatness does not depend on violating the territorial integrity and sovereignty of other countries?"

"I don't want to psychoanalyze Mr. Putin," Obama told a Buzzfeed reporter a few months earlier . "I will say that he has a foot very much in the Soviet past."

"That's how he came of age. He ran the KGB," Obama continued. "Those were his formative experiences. So I think he looks at problems through this Cold War lens, and, as a consequence, I think he's missed some opportunities for Russia to diversify its economy, to strengthen its relationship with its neighbors, to represent something different than the old Soviet-style aggression."

Obama's predecessor, George W. Bush, was also careful in his rhetoric with regard to Putin and Russia, sparing them from his so-called "axis of evil" designation and famously saying he looked into Putin's eyes and got "a sense of his soul."

Yet, as experts increasingly link Russia to hacks of US government systems, the Obama administration has been using stronger language to describe Russian behavior.

In an interview with NBC News earlier this week, Obama said it was "possible" the hacking of the DNC server was orchestrated on behalf of Russian intelligence services to influence the US election. "Anything's possible," he said.

"What we do know," he continued, "is that the Russians hack our systems. Not just government systems, but private systems."

The president's comment was the farthest the US government has gone to publicly blame Russia for carrying out cyber attacks on the US.

In a bid to discourage foreign government cyber attacks, the administration in recent years has pursued a "name and shame" policy, publicly attributing computer intrusions to government entities in China, North Korea and Iran. But not Russia.

Lisa Monaco, appearing Tuesday at a cyber-security conference hosted by the FBI and Fordham University in New York, said there wasn't a reluctance to name Russia. Determining attribution takes investigative work, which is ongoing, she said.

Russia, for its part, has denied allegations that it was involved with the DNC hack and trying to sway the US vote. "President Putin said numerous times that Russia has never interfered and doesn't interfere in domestic affairs of other countries, especially in electing campaigns," Kremlin spokesman Dmitry Peskov said . "Moscow carefully avoids any actions or words that might be seen as interference in an electoral process."

Senior administration officials, however, said they were fairly sure about Russian involvement in the hacking -- but that evidence tying them to WikiLeaks is less clear.

And they acknowledged the motive behind the hacking is not certain. Russia could have been trying to influence the election on behalf of Trump, if they carried it, or to make mischief more generally and create chaos during the election.

Officials stressed that the administration is only beginning to talk through a possible US response, which could involve cyber countermeasures. They added that sanctions are also possible but will not be easy to apply in a hacking case like this, particularly since the authority might not exist in the current Executive Order dealing with punishment for a cyber attack.

But the exploration of responses following US intelligence assessments that Russia is most likely behind the DNC hack, along with the comments by Biden and Obama, come at a time when the Democrats see a political opening in Trump's posture on Russia.

The GOP nominee has repeatedly made positive comments about Putin. And Biden's speech came hours after Trump called on Russian intelligence agencies Wednesday to share 30,000 of Hillary Clinton's deleted emails if they could find them. He said Thursday that the comment was sarcastic

Biden was only one of many speakers at the Democratic National Convention to use Putin to beat up on Trump.

Illinois Rep. Tammy Duckworth, who lost both her legs fighting in the Iraq War, told the Republican candidate from the stage Thursday evening: "Donald Trump, I didn't put my life on the line to defend our democracy so you could invite Russia to interfere in it. You are not fit to be the commander in chief."

The Democrats have seized on the DNC hack to allege that Putin has done it to help Trump.

The Trump campaign has rejected the speculation as "a deflection."