Jeff Sessions. REUTERS/Mark Kauzlarich

Jeff Sessions had two conversations with Russia's ambassador to the US during the 2016 campaign but did not mention it during his confirmation hearing for attorney general, The Washington Post reported on Wednesday night.

Sessions, then an Alabama senator, spoke with Sergey Kislyak in July and September, The Post reported. Yet during a confirmation hearing in January, Sessions said he "did not have communications with the Russians" while he served as a campaign surrogate for Donald Trump.

Lawmakers had already been calling for an independent investigation into Russia's election-related meddling and possible ties to various Trump associates. Just last month, Trump asked Michael Flynn to resign as national security adviser after it became clear Flynn had misled Vice President Mike Pence about having spoken with Kislyak about US sanctions on Russia before Trump was sworn in.

"I'm not aware of any of those activities," Sessions replied when asked during the hearing whether he knew about contacts between Russia and Trump's associates, which were at that point already being investigated by US intelligence officials.

"I have been called a surrogate at a time or two in that campaign and I did not have communications with the Russians," Sessions said.

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Sessions did not consider his conversation with Kislyak relevant enough to disclose at the hearing, his representative told The Post. Sessions did not even remember what he and Kislyak discussed, the person added.

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

The FBI was investigating Sessions' contacts with Russian officials before Trump nominated him in December, The Wall Street Journal reported on Wednesday. It is unclear whether that investigation is ongoing or whether the Senate was briefed on that investigation when it voted to confirm Sessions on February 8.

Sessions is now in control of the Justice Department and the FBI, each of which is investigating Russia's cyberattacks against the US. The House and Senate Intelligence Committees are also looking into the matter.

Sessions at a rally at the Ladd–Peebles Stadium, in Mobile, Alabama, on December 17. AP Photo/Brynn Anderson, file

Sessions has slapped away suggestions that he should recuse himself from the investigation. Republican Sen. Lindsey Graham commented on The Post's report during a CNN event on Wednesday night, saying "for sure you need a special prosecutor" if Sessions indeed spoke with the Kremlin.

"Misleading the Senate in sworn testimony about one's own contacts with the Russians is a good way to go to jail," Richard Painter, the chief White House ethics lawyer for President George W. Bush, said in a tweet on Wednesday.

Former White House national security adviser Michael Flynn seen February 13. REUTERS/Carlos Barria Sessions and Kislyak spoke as Russia was ramping up its hacking campaign against prominent Democrats, including the Democratic National Committee and Hillary Clinton's campaign chairman, John Podesta.

The Trump administration has repeatedly denied all suggestions that it colluded with Russia's interference activities. But The New York Times and CNN reported last month, citing US intelligence officials, that Russian operatives and people in Trump's inner circle communicated frequently before the election. The nature of the communication is unclear.

The Times last month reported that communications between people in Trump's orbit and Russia ran deep on both sides. They were said to include other associates of Trump outside his campaign. And on the Russian side, people within the country's government — in addition to intelligence officials — were also involved, according to The Times' sources, who remained anonymous.

Natasha Bertrand contributed to this report.