A scandal around the undisclosed contact between members of Donald Trump's team and Moscow has continued to snowball, most recently engulfing Attorney General Jeff Sessions.
The saga has taken observers on a helter-skelter ride – here is a run down of the key figures allegedly involved so far.
Mr Trump’s former campaign manager has worked for a string of controversial leaders, including pro-Russia Ukrainian leader, Viktor Yanukovych.
Mr Manafort was accused in July 2016 of agreeing to help soften US support for Ukraine in exchange for the Kremlin releasing information that would harm Hillary Clinton’s chances in the election.
The political consultant has also faced claimed he continued to take “kickback payments” from the former Ukrainian leader last year. He has denied all the charges.
In August 2016 The New York Times reported that Mr Yanukovych’s political party had set aside $12.7m (£10.3,) for Mr Manafort for his work between 2007-2012.
Mr Manafort said he never collected the payments, but five days later, for unspecified reasons, he resigned.
Lt Gen Michael Flynn
Mr Trump’s national security adviser resigned after only three weeks on the job.
He had come under increasing pressure to stand down after it was reported he discussed the issue of sanctions with the Russian ambassador.
He reportedly spoke five times with Sergey Kislyak on the same day Barack Obama announced sanctions against Moscow for its alleged attempt to influence the US election.
The former army man at first denied discussing the issue of sanctions, but eventually conceded that he “couldn’t be certain” sanctions were not discussed. He then apologised to the Vice President Mike Pence for misleading him.
Other media reports have since emerged that the US army was investigating whether Lt Gen Flynn took money from the Moscow on a trip to the Russian capital in 2015.
It has come to light that Attorney General Jeff Sessions met Russian ambassador Sergey Kislyak twice last year – encounters he did not disclose when asked directly about the issue at his confirmation hearing.
One of the meetings took place at the height to the alleged Russian cyber campaign attack against the US election.
Mr Sessions has denied wrongdoing, saying the reports were "unbelievable" and that he would only recuse himself from an investigation into Russian involvement in the election "whenever it's appropriate" to do so.
Oil industry consultant Carter Page was named as a foreign policy adviser to Mr Trump during his campaign, although Mr Trump has since denied giving him the job.
A report in July said Mr Page had attended a secret meeting with Igor Sechin, head of the Rosneft state-owned oil company and a long-term ally of Vladimir Putin.
Mr Page also allegedly met with Igor Divyekin, an internal affairs official, who was said to have warned Mr Page that Moscow had compromising material on the Mr Trump.
It has been alleged Mr Trump's personal lawyer Michael Cohen attended a secret rendezvous on 29 August with Russian officials at the offices of Rossotrudnichestvo, a Russian government cultural organisation.
Mr Cohen said he has never been to the Czech Republic and claimed he and his son at a baseball game on the date in question. The allegations have not yet been verified.
A long-running adviser to Mr Trump, Roger Stone has been named in news reports as one of at least four people the FBI was investigating for alleged contact with Russia.
Mr Stone said in a 2016 speech in Florida he had communicated with Julian Assange, the founder of WikiLeaks. The anti-secrecy group was behind the publication of hacked Democratic emails that badly affected Ms Clinton's presidential campaign.
During Mr Stone's speech, he predicted further leaks, a prediction that came true in the weeks that followed.
Mr Stone dismissed allegations he had ties to Russian intelligence as “nonsense” and has since called on the White House to launch an official inquiry into the Russian contact crisis.