Washington: Republican and Democrat lawmakers are demanding more information about connections between President Donald Trump`s former national security adviser Michael Flynn and Russia, a media report said.

Their calls come after months of controversy surrounding one of Trump`s longtime campaign advisers and top aide on security matters, CNN said in the report on Thursday.

Questions have swirled about the nature of his ties to Russia and whether he violated any restrictions on contacts with foreign officials.

Top Democrats and Republicans on the House Oversight Committee sent individual letters to four Trump administration officials requesting any documents they have related to Flynn`s communications with and payments from Russian, Turkish or other foreign sources.

"We are asking the Department of Defence and Federal Bureau of Investigation (FBI) and others to give us anything he has had to do with the Russian government and with Russians and others because he lied to us over and over again," Representative Elijah Cummings of Maryland told CNN on Thursday.

In the incident that led to his ouster in February from the National Security Council, Flynn acknowledged misleading Vice President Mike Pence about the nature of his communications with the Russian ambassador in Washington while Trump was still campaigning last year.

"We want to know what the President knew when he appointed him as security adviser," Cummings added.

Flynn had no comment regarding the committee`s letters, according to his spokesman Price Floyd.

Cummings and committee chairman Jason Chaffetz of Utah have asked that each agency produce documents relating to Flynn`s foreign contacts and payments, security clearance applications and other related documents between the time of his retirement in 2014 till now.

The committee has requested White House Chief of Staff Reince Priebus, FBI Director James Comey, Department of Defence Secretary James Mattis and Director of National Intelligence Daniel Coats to provide all documents by April 3.

Following initial reports in January that Flynn was in contact with Russian Ambassador to the US Sergey Kislyak and spoke to him about US sanctions, Vice President Mike Pence offered a robust defence of the incoming national security adviser, the CNN report said.

He said in nationally televised interviews that he had spoken with Flynn and that Flynn had ensured him he had not spoken about sanctions with the Russian ambassador.

The Justice Department, however, communicated to the White House that Flynn had misled administration officials.

Flynn wrote in his resignation letter that he had "inadvertently" briefed Pence and others in the White House with incomplete information about his contacts with Kislyak.

