President Trump's longtime lawyer Michael Cohen strongly denied claims in a dossier that he had a relationship with the Russian government and issued a line-by-line rebuttal of the document to Congress.

"We have not uncovered a single document that would in any way corroborate the dossier's allegations regarding Mr. Cohen, nor do we believe that any such document exists," Cohen's lawyer, Stephen Ryan, wrote in an eight-page letter to the House Intelligence Committee obtained by the New York Times. "Mr. Cohen vehemently denies the claims made in the dossier about him, which are false and remain wholly unsubstantiated."

Cohen denied the dossier's claim he met with a Russian official in Prague last summer. The letter says Cohen's passport does not have a stamp indicating he has visited the Czech Republic.

Cohen insisted the congressional committees and federal investigators looking into possible collusion between Trump associates and Russia look into who financed the infamous 35-page dossier, which was compiled by former British spy Christopher Steele. Most of the claims in the "Russia Dossier," which alleges collusion between the Trump campaign and Russia, have either been debunked, or are no longer taken seriously.

Among the documents Cohen gave to Congress were email communications from Felix Sater, a real estate broker with ties to Russia. Slater told Cohen in 2015 he could get Russian President Vladimir Putin's backing for Trump in the election.