WASHINGTON (AFP) - The US Justice Department on Thursday (June 8) said Attorney-General Jeff Sessions recused himself from the probe into Russia's attempt to influence the 2016 election only because of his involvement in President Donald Trump's election campaign.

Justice Department spokesman Ian Prior said "it was for that reason, and that reason alone" that Mr Sessions recused himself on March 2 from the Russian investigation.

The statement was released hours after former Federal Bureau of Investigation (FBI) director James Comey gave blockbuster testimony on alleged efforts by the President to influence the investigation into Russia's suspected meddling.

The Department of Justice statement did not mention Mr Sessions' contacts with Moscow's ambassador Sergey Kislyak, which he did not disclose during his confirmation hearing.

Mr Comey - who was sacked as FBI chief last month - told a Senate panel that he had thought Mr Sessions would recuse himself from the Russia probe earlier than he did, for undisclosed reasons that are classified.

Pressed on the attorney-general's "interactions with the Russians or his behaviour with regard to the investigation", Mr Comey said Mr Sessions "was very close to and inevitably going to recuse himself for a variety of reasons".

"We also were aware of facts that I can't discuss in an open setting that would make his continued engagement in a Russia-related investigation problematic," Mr Comey said.

In its statement, the department emphasised that since recusing himself, Mr Sessions "has not been briefed on or participated in any investigation within the scope of his recusal".

Mr Sessions offered to resign recently, telling Mr Trump he needed the freedom to do his job, US media reported earlier this week.

Following the reports, the White House declined to say whether the President still had confidence in the attorney-general.