A number of well-connected Russian nationals with ties to Vladimir Putin were reportedly in attendance at the President's inauguration last year and the FBI is reportedly trying to figure out why.

Days before Donald Trump's swearing in ceremony, The Washington Post reports that at least half-a-dozen powerful Russian figures and activists arrived in the nation's capital to mark the ushering in of the new administration.

Social media posts on Facebook, for example, show Russian pharmaceutical executive Alexey Repik, along with his wife, Polina, boasting of their prime access to festivities and politicians during their week long excursion.

Days before Donald Trump's swearing in ceremony, at least half-a-dozen powerful Russian figures and activists were in Washington

Social media posts on Facebook, for example, show Russian pharmaceutical executive Alexey Repik, along with his wife, Polina, boasting of their prime access to festivities

Repik was fortunate enough to witness the swearing-in ceremony from ticketed seats in front of Capital Hill and later posed shoulder-to-shoulder with Trump's then nominee for CIA Director, Mike Pompeo, for a picture.

He also posed shoulder-to-shoulder with Trump's then nominee for CIA Director, Mike Pompeo (L), for a picture.

'I believe that President Donald Trump will open a new page in American history,' Repik wrote in one post while holding a clutch of inauguration passes arranged next to a white 'Make America Great Again' in Russian.

The presence of other high-profile Russians such as business tycoon Viktor Vekselberg and Natalia Veselnitskaya, the Russian lawyer whose June 2016 meeting at Trump Tower with Donald Trump Jr. has become a focus of a special counsel investigation, reportedly raised red flags among security officials in Washington.

The FBI expressed concern at the time because some of the individuals had surfaced in the agency's investigation of the Trump campaign's ties to Russia, according to former U.S. officials who spoke to the Post under the condition of anonymity.

Other guests with Kremlin ties included Boris Titov, a politician and business advocate who is running for president of Russia with Putin's blessing, according to The Post.

The presence of high-profile Russians such as business tycoon Viktor Vekselberg (L) and Natalia Veselnitskaya (R) also raised concerns in the FBI

Other guests with Kremlin ties included Boris Titov (R), a politician and business advocate who is running for president of Russia with Putin's blessing (Pictured along with his wife Yelena 2017)

'It was a great, amazing experience,' Repik later told the Post in an interview. He also said that he was in Washington in 2013 during former President Barack Obama's inauguration, but did not attend any events.

At the same time, Russian officials in Moscow were celebrating Donald Trump's victory, popping open champagne bottles and looking forward to dealing with an administration with an 'America First' attitude that emphasized more on business and domestic issues instead of promoting democracy abroad, the Post reported.

A year later, however, sanctions placed on Russia by the Obama administration are still in place and US special prosecutor Robert Mueller is still investigating possible collusion allegations between the Trump campaign and the Kremlin.

Donald Trump taking the oath of allegiance during his swearing-in ceremony on January 20, 2017 at the US Capitol in Washington, DC

'We hoped that a lot of things would change, that the relations would be built on equal terms, that we would be able to start a new stage in the relations between countries,' Titov said in an interview. 'But unfortunately, this is not happening.'

Titov refused to reveal how he received an invitation to the inauguration or any of the events held that day, saying only that he came 'via our friends — entrepreneurs in the Republican Party.'

A spokesperson for Vekselberg, head of the Renova group - which oversees business interests in energy, telecom and mining - said the Russian billionaire attended Trump's inauguration as a guest of 'one of his closest American business partners.'

The spokesperson refused to reveal who the American business partner was.

Vekselberg reportedly has close ties to Vladimir Putin and his inner circle, regularly participating in gatherings of Russian business leaders at the Kremlin and occasionally holding private meetings with the powerful Russian leader.

Russian officials in Moscow were celebrating Donald Trump's victory, opening champagne and looking forward to dealing with an administration with an 'America First' attitude