WASHINGTON — President Donald Trump’s ex-attorney will return to Congress next week for more testimony, US lawmakers said on Thursday, after three days of marathon appearances during which Michael Cohen accused his longtime boss of being a conman engaged in illegal activity.

House Intelligence Committee chairman Adam Schiff also revealed that Felix Sater, a Russian-born real estate developer who claims strong connections to the Kremlin, and who reportedly pitched the Moscow Trump Tower project to Trump’s team, will testify before the committee on March 14.

The public hearing is believed to be the first scheduled appearance before Congress for Sater, who once had an office in Trump Tower and is seen as a mysterious figure who could shed light on dealings between the Trump organisation, his campaign and Russia.

Cohen meanwhile will return on March 6 for additional closed-door testimony to the Intelligence Committee, Schiff said.

"It was a very productive interview today, where he was able to shed light on a lot of issues that are very core to our investigation, and we were able to drill down in great detail," Schiff said, adding that he intented to publicly release transcripts of Cohen’s testimony "at the appropriate point."

Speaking in Việt Nam after a summit with North Korea’s Kim Jong Un, Trump sought to discredit Cohen, saying his former lawyer and fixer had "lied a lot" -- although not about "one thing."

"He said, no collusion with the Russian hoax," Trump said. "And I said, I wonder why he didn’t lie about that, too, like everything else."

The president did not address any of Cohen’s specific, explosive allegations about his decade of working with Trump.

On Thursday, two Republicans on the House Oversight Committee said they had petitioned the Justice Department to investigate Cohen for perjury.

They alleged that he lied in Wednesday’s testimony about his alleged desire to get a job in the Trump White House, and about whether he had committed bank fraud in the past.

Cohen’s lawyer Lanny Davis rejected their claims.

"Mr. Cohen testified truthfully before the House Oversight Committee.... He also backed up much of his testimony with documents," Davis said, calling the complaint "baseless." — AFP