US President Donald Trump's former national security advisor, Michael Flynn, is in discussions with the House and Senate intelligence committees to testify about possible ties between the Trump campaign and Russia in exchange for immunity from "unfair prosecution," his attorney said on Thursday.

"General Flynn certainly has a story to tell, and he very much wants to tell it, should the circumstances permit," Flynn's lawyer, Robert Kelner, said in a statement.

Flynn's relations with Russia are being investigated by the Federal Bureau of Investigation (FBI) and both the House and Senate intelligence committees. The investigations are probing alleged Russian interference in last year's election and possible ties between the Trump campaign and the Kremlin.

Flynn was forced to resign in February for not disclosing conversations he had with Russian Ambassador to the United States Sergei Kisylak about US sanctions. At the time of the conversations, Flynn was the national security adviser for Trump's presidential campaign. He stepped down after it was revealed that he misled Vice President Mike Pence about his contact with Russian officials.

"Witch hunt environment"

Kelner said his client "is now the target of unsubstantiated public demands by Members of Congress and other political critics that he be criminally investigated."

He added Flynn would not "submit to questioning in such a highly politicized, witch hunt environment without assurances against unfair prosecution."

Moscow denies any role in manipulating the US election with Russian President Vladimir Putin using a peculiar quote to make the point on Thursday. 

The Trump administration has accused Democrats of pursuing a politically motivated investigation because they lost the election.

Read: Constant information drip deepens Donald Trump's Russian woes

Kelner released the statement after "The Wall Street Journal" reported Flynn was seeking immunity from the FBI and House and Senate intelligence committees.

Conflicting statements

The House Intelligence Committee denied the report. "Michael Flynn has not offered to testify to HPSCI in exchange for immunity," committee spokesman Jack Langer said in a statement.

However, speaking to the AP news agency, a congressional aide confirmed on condition of anonymity that there have been discussions with the Senate intelligence committee about immunity.

Kelner did not mention the FBI and the law enforcement body declined to comment.

Ahead of the 2016 US presidential election, Flynn said it was unacceptable that some of Democratic candidate Hillary Clinton's aides requested immunity in exchange for providing information regarding a private email server Clinton used while serving as secretary of state. 

"When you get given immunity that means you've probably committed a crime," he told NBC News in September.

cw/sms (AFP, AP, Reuters)

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