US Attorney General Jeff Sessions is the latest member of Donald Trump's administration to come under fire for contact with Russian officials after sources told the Washington Post that the then-Alabama Senator spoke twice with Russia's Ambassador to the US during the presidential campaign.

During his confirmation hearing, Sessions pointedly told Senator Al Franken that he had not had communications with Russian officials and when asked what he would do if he discovered such information about anyone in the campaign team, he said: "I have been called a surrogate at a time or two in that campaign and I did not have communications with the Russians."

Sessions and Sergey Kislyak, the Russian Ambassador, had two meetings - one occurring in July and one in September. At the time, Sessions was a member of the Armed Services Committee.

"I never met with any Russian officials to discuss issues of the campaign. I have no idea what this allegation is about. It is false," Sessions said in a statement Wednesday evening.

Session's spokespeople told the paper that they did not believe the meetings were relevant to the hearing question, arguing that they took place in his capacity as Senator and member of the committee, not as part of the Trump campaign.

The new information puts into question Sessions' continuing refusal to recuse himself from investigations into links between Russia and the Trump campaign team. The investigation has so far been led by the FBI, overseen by Sessions in his position as Attorney General.

Sessions' contact with Kislyak has also been revealed only weeks after General Michael Flynn was forced to resign his post as national security adviser over revelations that he spoke with Ambassador Kislyak about lessening US sanctions against Russia before he had taken public office.

Questions of Flynn's contact were made particularly difficult for the administration when it turned out that senior officials, including Vice President Mike Pence, had been misled as to the content of the calls.

Senator Franken told the Post that if the contact was true, he was "troubled" by Sessions' answer to his questioning over the Trump team's Russia ties, describing it as "at best, misleading". The Senator also added that Sessions "must recuse himself immediately" from any investigation.