President Donald Trump denied Friday that he knew in advance about a meeting during the 2016 election campaign at which Russians promised to share dirt on his rival Hillary Clinton - shooting back at an explosive allegation by his longtime lawyer.
Trump's son-in-law Jared Kushner, son Donald Jr, and top campaign official Paul Manafort met at Trump Tower in New York on June 9, 2016 with Russian lawyer Natalia Veselnitskaya, who had said she was offering information from the Russian government aimed at helping Trump to victory.
The US president has repeatedly denied all knowledge of the encounter, but according to television networks CNN and NBC, his former lawyer Michael Cohen says Donald Jr told his father about the Russian offer and that Trump approved.
"I did NOT know of the meeting with my son, Don jr," the president countered in a tweet early Friday.
"Sounds to me like someone is trying to make up stories in order to get himself out of an unrelated jam," Trump said.
The assertion from Cohen, who is under federal investigation in New York, is potentially important. If substantiated, it could be a key step toward proving collusion between the Trump campaign and a Russian effort to help Trump win the presidency - a central focus of a probe by special counsel Robert Mueller.
CNN and NBC News reported that Cohen was willing to attest what he knows to Mueller, but CNN said the long-time Trump fixer does not have evidence, such as audio recordings, to corroborate his claim.
Trump's new personal lawyer, former New York mayor Rudy Giuliani, told CNN that Cohen had "been lying for years" and rubbished his credibility.
The president, his son, his lawyers and other administration officials have repeatedly said Trump did not know about the meeting.
Coming days after Cohen's lawyer leaked a taped conversation between his client and Trump, there is growing speculation that Cohen may be keen to cooperate with prosecutors, and how much damage he can inflict on his former boss.
The Trump Tower meeting was arranged by British music promoter, Rob Goldstone, who told Trump Jr that he had "information that would incriminate Hillary and her dealings with Russia and would be very useful to your father."
Trump Jr responded "I love it" when first offered the "dirt" on Clinton, the Democratic nominee. News of the meeting broke in July 2017.
The president's son has said since that no "meaningful information" was offered and that the meeting focused mostly on adoptions of Russian children.
Mueller has already indicted more than 30 people, including 12 Russian intelligence agents earlier this month for allegedly hacking Clinton's campaign and the Democratic Party.
The New York Times has reported that Mueller is investigating whether Trump's tweets about Attorney General Jeff Sessions and former FBI director James Comey constitute an attempt to obstruct justice.
Manafort has been the first former Trump campaign aide jailed. A US federal judge last month revoked his bail over claims he was tampering with witnesses, as he awaits trial on money laundering, tax and bank fraud charges.
Trump, who is accused at home of being too pliant toward Russian President Vladimir Putin, insists no president has been as "tough" on Russia and denies any collusion between his campaign and Moscow.
The White House said Friday that Trump was "open" to visiting Moscow after Putin said in South Africa that he had invited the US leader to the Russian capital and was ready to meet him also in Washington.
Later Friday, Trump is to gather his National Security Council for a meeting on election security, as US intelligence chiefs warn Russia will seek to meddle again in the November midterm polls.
Earlier this week, Cohen's lawyer leaked to CNN a taped conversation between the former lawyer and Trump, and told ABC News that his client had "more tapes."
On the leaked recording, Trump and Cohen discuss buying the rights to a story that Playboy model Karen McDougal had an affair with Trump in 2006.
The conversation was taped two months before the election, despite Trump's campaign subsequently denying any knowledge of the deal.
The payment would have essentially reimbursed the parent company of the National Enquirer which bought the rights to her story for $150,000. No evidence has yet emerged publicly that the Trump-Cohen payment was made.
Cohen is under investigation for his business dealings and reportedly whether a $130,000 hush payment to porn star Stormy Daniels, just days before the election, violated campaign finance laws.