Michael Cohen in closed-door testimony Wednesday handed over documents to substantiate his claim that his false testimony to Congress in 2017 was altered by President Donald Trump's attorneys, a source familiar with the matter told Business Insider.

Cohen told lawmakers last week that Trump's then-attorney, Jay Sekulow, edited his 2017 statement before he delivered it to lawmakers. Sekulow denies doing so.

In December, Cohen was sentenced to seven years in prison for crimes including lying to Congress and paying hush money to women who claimed to have had affairs with Trump.

Michael Cohen has handed over documents to lawmakers to substantiate his claim that President Donald Trump’s attorneys altered his false statement to Congress last year.

The statement was about a planned Trump real estate project in Moscow, about which Cohen testified in 2017, a year before his current round of hearings.

A source familiar with the matter confirmed to Business Insider Thursday that Cohen, Trump’s former personal attorney and fixer, handed the documents over during closed-door testimony to the House Intelligence Committee on Wednesday.

During testimony to the House and Senate Intelligence Committee in 2017, Cohen had falsely claimed that discussions about a multimillion dollar Trump Tower project in Moscow had taken place no later than January 2016, as Trump was running for the Republican nomination for the presidency.

He later confirmed to prosecutors, discussions had been taking place until at least June of 2016.

As part of his dramatic public testimony to the House Judiciary Committee last week, Cohen claimed that Jay Sekulow, who was then serving as Trump’s personal attorney, in 2017 edited his statement before he delivered it to Congress.

Sekulow in a statement last week pushed back against Cohen’s allegation.

"Testimony by Michael Cohen that attorneys for the President edited or changed his statement to Congress to alter the duration of the Trump Tower Moscow negotiations is completely false,” he said.

The documents Cohen submitted on Wednesday reportedly relate to the claims.

It has not been disclosed exactly which of the statements Cohen made before the House and Senate Intelligence Committees in 2017 he claims were altered.

Cohen had returned to answer further questions by the committee Wednesday after seven hours of testimony last week.

In a statement released Wednesday night Cohen's attorney, Lanny Davis, said his client had answered lawmakers’ questions “truthfully,” and would provide the panel with additional information.

It said: "Mr. Cohen has now spent 16 hours with the HPSCI answering many questions from both Republicans and Democrats. Mr. Cohen responded to all questions truthfully and has agreed at the request of chairman Schiff to provide additional information in the future, if needed.

"He also offered to answer additional questions from Republican members. He remains committed to telling the truth and cooperating with authorities.”

Davis in an interview Wednesday confirmed that Cohen's former attorney, Stephen Ryan, had reached out to Trump's lawyers about the possibility of receiving a presidential pardon before an April raid on his home and offices by prosecutors seeking evidence of hush money payouts.

Democratic House Intelligence Committee Chairman Adam Schiff told reporters after Cohen’s testimony Wednesday that he had provided new documents, but would not disclose their contents.

“We had requested documents of Mr Cohen. He has provided additional documents to the committee. There may be additional documents that he still has to offer and his cooperation with our committee continues,” Schiff said.

Cohen in November pleaded guilty to charges of lying to congress and election crimes filed by special counsel Robert Mueller and New York prosecutors and was sentenced to three years in prison.