President Donald Trump branded Democrats "hypocrites" over calls for an investigation into his administration's contacts with Russia, posting a photograph on the internet of one of the opposition party's leaders sharing doughnuts and coffee with Vladimir Putin.
It came after half a dozen Trump officials and advisers were revealed to have met Sergey Kislyak, the Russian ambassador to Washington, in the six months before the president took office.
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Mr Trump responded by posting the picture on Twitter showing Chuck Schumer, the Democratic leader in the US Senate, smiling alongside Mr Putin during his trip to New York in 2003.
The president said: "We should start an immediate investigation into Senator Schumer and his ties to Russia and Putin. A total hypocrite!"
Not satisfied with that, then president then pointed the finger at Democratic leader in the House of Representatives, Nancy Pelosi.
I hereby demand a second investigation, after Schumer, of Pelosi for her close ties to Russia, and lying about it. https://t.co/qCDljfF3wN— Donald J. Trump (@realDonaldTrump) March 3, 2017
Mr Schumer said he would "happily talk under oath" about his encounter with Mr Putin, and asked Mr Trump: "Would you?"
It came as Jared Kushner, the president's son-in-law and senior adviser, became the latest figure drawn into the web of entanglements with Russian officials that has plagued the new administration.
The 36-year-old husband of Mr Trump's daughter Ivanka, was present at a previously undisclosed meeting between Michael Flynn, Mr Trump's former national security adviser, and Mr Kislyak at Trump Tower in New York in December.
Mr Flynn resigned last month after it emerged he had misled Vice President Mike Pence about the extent of his communications with Mr Kislyak. In the December meeting the Russian diplomat reportedly entered Trump Tower by a back entrance and spoke for between 10 and 20 minutes.
The White House said the intention was to “establish a line of communication” with the Russian government. One official called it an "inconsequential hello" and said Mr Kushner had not met Mr Kislyak since.
On Thursday Attorney General Jeff Sessions recused himself from any future investigation examining communications between Trump officials and Moscow.
He did so after it was revealed he had himself spoken twice to Mr Kislyak and not revealed it during the confirmation hearing for his new post.
Mr Sessions was accused of "lying under oath" by Democrats in Congress who called on him to resign.
Several other Trump campaign advisers - national security advisers JD Gordon and Walifd Phares, and former foreign policy adviser Carter Page - also spoke with Mr Kislyak at the Republican National Convention in Cleveland last July, it emerged.
Mr Gordon said there was nothing inappropriate about them having done so.
The Kremlin indicated its disappointment and frustration at how the uproar was blocking progress on US-Russian relations, including on the issues of Syria and combating terrorism.
It furiously denied allegations that Mr Kislyak, who emerged as the central figure in a controversy, was a spy. Senior intelligence officials told CNN the amiable career diplomat, at one time the Russian envoy to Nato, was suspected of being one of Russia's top espionage recruiters in Washington.
Russian Foreign Ministry spokeswoman Maria Zakharova responded by saying: "Recruiting? Oh my God! Stop spreading lies and false news. He is a well-known, world-class diplomat.
"I'll open a military secret for you - it's the diplomats' jobs to have contacts in the country they are posted to."
Russian Foreign Minister Sergey Lavrov said Mr Kislyak was doing his job meeting senior US officials.
He added: "This strongly resembles a witch hunt or the times of McCarthyism which we thought were long over in the United States as a civilised country."
Steve Hall, former former chief of Russian operations for the CIA, said: "Ambassador Kislyak is clearly an aggressive guy, getting out there and talking to as many people as he possibly can, that's what Vladimir Putin wants him to do."
Mr Hall added: "It's an interesting effect he had on people. They have meetings with him and then they forget. It's pretty amazing."