President Trump said Wednesday morning he is nominating former Justice Department official Christopher Wray for FBI director to replace James Comey, who was abruptly fired last month as he conducted an investigation into possible collusion between Trump campaign associates and Russia.

The president made the announcement early Wednesday morning via Twitter.

"I will be nominating Christopher A. Wray, a man of impeccable credentials, to be the new Director of the FBI," Trump tweeted. "Details to follow."

A former chief of the Justice Department's Criminal Division from 2003 to 2005, Wray served during the administration of President George W. Bush. During his time in the government, Wray was a member of the administration's Corporate Fraud Task Force and oversaw the fraud prosecutions of former executives at Enron Corp.

Trump's announcement comes the same day top intelligence officials testify on Capitol Hill, and a day before former director Comey is due to testify about the Russia investigation and the circumstances behind his dismissal.

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"I think it's more than a little curious,' said Sen. Mark Warner (D-Virginia). "It appears that the president is trying to change the topic because we have two days of hearings here that could be explosive."

In Wednesday's hearing, Director of National Intelligence, Dan Coats faces questions about a Washington Post report which says the president asked him to intervene in the Russia probe. The Post article says Trump went to Coats after asking Comey to back off of the Russia investigation into former National Security Advisor Michael Flynn.

In a statement, Coats says he never felt pressured by the Administration while not denying the conversation happened.

Comey is expected to say that Trump asked him to ease up on an investigation of former National Security Adviser Michael Flynn, who is involved in the Russia probe.

A special counsel, former FBI Director Robert Mueller, is heading up an investigation into links between Trump's presidential campaign last year and Russians who sought to influence the election by hacking Democrats. Various congressional committees are also investigating.'

USA Today & NBC News contributed to this report.