A combination photo shows US President Donald Trump (L) in the House of Representatives in Washington, US, on February 28, 2017 and FBI Director James Comey in Washington US on July 7, 2016. [Photo/Agencies]

WASHINGTON - The White House on Tuesday pushed back against a new wave of media allegations that US President Donald Trump might have tried to obstruct justice by asking then FBI director James Comey to end a probe into former national security adviser Michael Flynn.

"I hope you can let this go," Trump told Comey at the time, according to a New York Times report, quoting two people who read the memo Comey wrote shortly after meeting with Trump in the Oval Office one day after Flynn resigned over a Russia-related scandal in February.

Comey, who was fired by Trump last week, detailed his conversation with the president in the memo immediately after the meeting, said the report.

Jason Chaffetz, Republican chairman of the House Oversight Committee, said on Tuesday that he is requesting the FBI to submit all the files and recordings involving any communications between Comey and Trump.

However, the White House quickly denied the report, claiming it is "not a truthful or accurate portrayal of the conversation between the president and Mr Comey".

"While the president has repeatedly expressed his view that General Flynn is a decent man who served and protected our country, the president has never asked Mr Comey or anyone else to end any investigation, including any investigation involving General Flynn," the White House said in a statement.

"The president has the utmost respect for our law enforcement agencies, and all investigations," it said.

Despite the denial, the latest allegation immediately feeds fresh fuel to the flames that have been grilling the White House since Trump's firing of Comey last week, distracting his agenda while plunging his administration into a fast accumulating credibility crisis.

On Monday, it was alleged that Trump relayed highly classified information from a critical source of intelligence on the Islamic State group in Iraq and Syria during his meeting with senior Russian officials last week.

'Absolute right'

Trump tweeted that he has "the absolute right" to share certain information with Russia but also didn't specifically say whether he spilled highly classified information to Russian officials. Indeed, as US president, Trump has broad authority to declassify government secrets, making it unlikely that such disclosures broke the law.

However, a trust crisis is looming large if the Trump can't control damage soon.

The White House is in a "downward spiral" and needs to do something to get "under control", Republican Senator Bob Corker has said.

"On a day when we thought things couldn't get any worse, they have," Senate Minority Leader Chuck Schumer said on Tuesday. "The country is being tested in unprecedented ways."

Though Republican lawmakers have so far generally backed Trump, a new mood was evident on Capitol Hill, a Politico report commented.

Also on Tuesday, a new poll showed that 48 percent of US voters said they would support Trump's impeachment, while only 41 percent would oppose such charges.

Xinhua