James Comey, the former FBI director who was fired this week by U.S. President Donald Trump, declined an invitation from the Senate Intelligence Committee to testify on the matter on Tuesday, 16 May, after Donald Trump warned him against speaking out.

The committee, which is in the process of an investigation into Russian interference in the 2016 election, had hoped to hear from Comey in closed session. Comey oversaw the FBI’s investigation of alleged Russian meddling in the election.

Meanwhile Trump said today he will move quickly to nominate a new FBI director, after he sparked a political firestorm by firing the man investigating possible collusion between Russia and the Trump presidential campaign.

Critics have assailed Trump for abruptly dismissing Comey, who was leading the agency’s investigation into alleged Russian meddling in the 2016 U.S. election, and possible ties between Moscow and the Trump presidential campaign.. Russia denies the claims and the White House says there was no collusion.

Democrats cast the decision to fire Comey as an effort to obstruct the FBI’s probe, a charge the White House has denied.

While Democrats have called for an independent special counsel to investigate the Russia matter, most Republicans have said that is not necessary given the FBI probe and investigations in both the House and Senate.

White House officials initially said Trump acted on a Justice Department recommendation, but the president later said he would have fired Comey anyway, calling the former FBI chief a “showboat.”

A White House official has said Trump is considering 11 people to replace Comey. Acting FBI Director Andrew McCabe, Republican Senator John Cornyn, New York Appeals Court Judge Michael Garcia and former Assistant Attorney General Alice Fisher will be interviewed on Saturday for the post, an administration official said.

The decision is subject to confirmation by the U.S. Senate, where Republicans have a majority.