The president is under pressure after two law enforcement officials involved in special counsel Robert Mueller’s probe into Russian collusion in the 2016 US election claimed to have obtained evidence of possible obstruction.
Several Democrats have urged Congress to seek clarification of what information the special counsel may hold on the matter, with one calling for Mr Trump to be removed if the claims, first published by Buzzfeed News, are proven.
California representative Adam Schiff said Congress would “do what’s necessary” to find out if the contents of the report were true.
“The allegation that the President of the United States may have suborned perjury before our committee in an effort to curtail the investigation and cover up his business dealings with Russia is among the most serious to date,” he added.
“If the @BuzzFeed story is true, President Trump must resign or be impeached,” Texas congressman Joaquin Castro wrote on Twitter.
If the @BuzzFeed story is true, President Trump must resign or be impeached.
— Joaquin Castro (@JoaquinCastrotx)
Chris Murphy, a Democratic senator from Connecticut, urged the Mueller probe to confirm whether it had evidence the president instructed his lawyer to lie to Congress.
“If Mueller does have multiple sources confirming Trump directed Cohen to lie to Congress, then we need to know this ASAP,” he said.
“Mueller shouldn't end his inquiry, but it's about time for him to show Congress his cards before it's too late for us to act.”
Special counsel sources have reportedly learned Mr Trump planned to visit Moscow during the 2016 election campaign, where he would meet with Russian president Vladimir Putin and kick-start negotiations over the tower project, telling Cohen to “make it happen”.
The president has routinely denied he had business ties to Russia after the point at which he secured the Republican candidcacy.
However, Cohen, who cooperated with the Mueller investigation after pleading guilty to committing campaign finance violations during the 2016 election, has reportedly told the special counsel Mr Trump instructed him to lie over his contact with Moscow during testimony to Congress.
Sources said the investigation had been able to corroborate Cohen’s assertions using interviews with additional witnesses from inside the Trump Organisation, as well as information in internal emails, text messages and other documents.
Cohen had previously told a Senate committee the project to build a Trump Tower in Moscow had been scrapped in January 2016.
But, he later admitted during court proceedings this statement was untrue and he had been involved in negotiations over the project until at least July that year- two months after Mr Trump had been declared the presumptive Republican nominee for president.
It appeared until now the special counsel had not found any evidence Mr Trump was personally involved in his attorney’s decision to lie to Congress.
However, if true, these new reports suggest Cohen has provided testimony to investigators that has the potential to implicate the president himself in the scandal.
California congressman, Ted Lieu, called on the House Judiciary Committee to stage an investigation to establish whether Mr Trump had been involved in any illegality.
“This stunning Trump Tower Moscow story establishes a clear case of Obstruction of Justice, a felony. I've lost count now how many times @realDonaldTrump has engaged in Obstruction of Justice,” he added on Twitter.