House Oversight Committee Democrats released documentation that they say shows fired Trump national security advisor Michael Flynn falsely claimed 'U.S. companies' paid for his 2015 Moscow trip funded by a Kremlin-backed firm.

The charge that Flynn made false statements during his federal background check to work in the Trump White House came on a day when Flynn's lawyer said Flynn would plead the Fifth Amendment rather than testify before a congressional committee probing Russian election interference.

Flynn infamously traveled to Moscow in 2015 to attend an anniversary gala for RT, the Kremlin-backed network, and was seated next to Russian president Vladimir Putin at the event.

Asked during his security check check about payment, Flynn told his interviewers: 'I didn't take any money from Russia, if that's what your'e asking me,' according to the letter from Maryland Rep. Elijah Cummings, the top panel Democrat.

Former National Security Advisor Michael Flynn will use the Fifth Amendment to shield himself from having to hand over documents to a Senate committee

It has previously been revealed that Flynn got paid $45,000 by RT for the gig.

RT transferred the funds through a London-based bank to Leading Authorities, which represented Flynn for speaking engagements, according to the letter.

An RT official stated in an email that 'We will be covering the payment of General Flynn's fees.'

Documents obtained by the committee also show that 'RT paid directly for General Flyn's airfare, lodging at the Metropol Hotel in Red Square, and other expenses for both him and his son. These benefits were not routed through General Flynn's speakers' bureau.'

Quoting from the internal Report of Investigation, the letter states that Flynn told investigators trips to Japan and Saudi Arabia were also funded by 'U.S. companies.'

In a quote Cummings threw back at committee GOP chair Rep. Jason Chaffetz of Utah, Trump tried to blame the Obama administration for Flynn, since his security clearance got renewed by security officials in 2016, before Trump took office.

'Obama, I guess, didn't vet, cause he was approved at the highest level of security by the Obama Administration,' Trump told Fox News.

Michael Flynn (center), flanked by President Trump's aides Stephen Miller (left) and Jared Kushner (right), will not comply with a subpoena seeking documents

The investigatory report states that Flynn stated that 'HE does not have any foreign business connections or foreign financial interests. HE has not received any benefit from a foreign country.'

According to the report, Flynn also 'Did not reveal any substantial contacts with foreign nationals.'

According to the Democratic letter, 'It is difficult to understand how General Flynn could have believed that his dinner with Russian President Vladimir Putin was an "insubstantial contact."'

Attorneys for Michael Flynn say that a daily 'escalating public frenzy against him' and the Justice Department’s appointment of a special counsel have created a legally dangerous environment for him to cooperate with a Senate investigation.

That’s according to a letter obtained by The Associated Press that was written on behalf of the former national security adviser under President Donald Trump.

The letter, sent Monday by Flynn’s legal team to the Senate Intelligence committee, lays out the case for Flynn to invoke his Fifth Amendment protection against self-incrimination and his decision not to produce documents in response to a congressional subpoena.

NBC News reported Monday that two other close Trump associates, Roger Stone and Paul Manafort, handed documents over to the Senate Intelligence Committee.

The Flynn letter says that the current context of the Senate’s investigation into Russia’s meddling in the 2016 election threatens that 'any testimony he provides could be used against him.'

Earlier Monday the AP reported that Flynn would invoke his Fifth Amendment protection against self-incrimination as he notified the Senate Intelligence committee that he will not comply with a subpoena seeking documents.

That's according to a person with direct knowledge of the matter.

The person spoke on condition of anonymity to discuss the private interactions between Flynn and the committee.

Flynn's decision comes less than two weeks after the committee issued a subpoena for Flynn's documents as part of the panel's investigation into Russia's meddling in the 2016 election.

The Senate's No. 2 Republican, Sen. John Cornyn of Texas, downplayed any talk of holding Flynn in contempt of Congress for refusing to comply.

'It's his constitutional right,' Cornyn told reporters Monday, according to The Hill.

Legal experts had said Flynn was unlikely to turn over the personal documents without immunity because he would be waiving some of his constitutional protections by doing so.

Flynn has previously sought immunity from 'unfair prosecution' to cooperate with the committee.

He made the same offer to the House committee, which is looking into Russian election interference and Trump campaign links.

Neither has agreed to give the former national security adviser immunity.

'As with any investigation – and particularly one that grows in severity and magnitude by the day – there is still much work and many more witnesses and documents to obtain before any immunity request from any witness can be considered,' House Intelligence Committee ranking member, Rep. Adam Schiff, D-Calif., said in March.

Trump tweeted that he was in support of Flynn having immunity.

'Mike Flynn should ask for immunity in that this is a witch hunt (excuse for big election loss), by media & Dems, of historic proportion!' Trump wrote.

Flynn was fired from the White House in February after misleading Vice President Mike Pence over conversations he had during the transition with Russian ambassador Sergey Kislyak, on the heels of President Obama announcing new sanctions against Russia over election meddling.

Former acting Attorney General Sally Yates warned the White House several days after Trump's swearing-in that Flynn had deceived Pence – and the Russians knew about it – making his susceptible to blackmail.

Yates was dismissed shortly thereafter by President Trump for refusing to defend his travel ban, which impacted only Muslim-majority countries.

Once Yates' conversations with the White House over Flynn became public, Trump let his national security adviser go on Feb. 13.

Since then, Trump has lamented letting Flynn go, according to reporting from Politico.

But the former national security adviser has continued to be a thorn in Trump's side, politically, as Trump took a hit for reportedly asking now ex-FBI Director James Comey to quit looking into Flynn, before controversially firing the FBI head.

During a press conference last week, Trump denied that allegation.

'No, no, next question,' Trump told WJLA's Scott Thuman.

With a special counsel now chosen to continue the FBI's Russia probe, and two investigations proceeding on Capitol Hill, Flynn, who Trump calls a 'good man,' won't be untangled from this administration anytime soon.