US Attorney General Jeff Sessions has denied during a Congress hearing having undisclosed meetings with Russian officials at a Washington DC hotel.
America’s top law official also told the Senate Intelligence Committee any suggestion he colluded with the Kremlin was “an appalling and detestable lie”.
His remarks come days after sacked FBI boss James Comey said he believed he was fired to change the Russia probe.
Mr Sessions had recused himself from any probe in Russia’s alleged meddling.
The Senate committee is of one several congressional panels that, along with a special counsel, is also investigating whether any Trump campaign officials colluded with the alleged Kremlin plot.
“I recused myself from any investigation into the campaigns for President, but I did not recuse myself from defending my honour against scurrilous and false allegations,” Mr Sessions said in an opening statement on Tuesday.
Mr Sessions acknowledged he met Russian Ambassador Sergei Kislyak twice, but suggested he could not remember whether he met the envoy at a foreign policy speech event for then-candidate Donald Trump at the Mayflower Hotel on 27 April 2016, as US media have reported.
“I do not have any recollection of meeting or talking to the Russian Ambassador or any other Russian officials. If any brief interaction occurred in passing with the Russian Ambassador during that reception, I do not remember it,” he told senators.
He also rejected claims that he lied to Congress during his confirmation hearing when he suggested he had no contact with Russian officials, contending that it was a “fair and correct response for the question as I understood it”.
The former Alabama senator also denied he offered his resignation when Mr Trump was reportedly angered by his recusal from the FBI Russia probe, telling the panel he “will not be deterred”.
Vice-Chairman Senator Mark Warner, a Democrat, pressed Mr Sessions about his role in the sacking of Mr Comey.
Mr Sessions said he never spoke to the former FBI director, who reports to Mr Sessions, about his job performance before Mr Trump fired him in May.
But the US attorney general did confirm Mr Comey’s testimony that he alerted Mr Sessions, his boss, that he felt uncomfortable speaking directly to Mr Trump in a one-on-one setting.
Jeff Sessions denies third meeting with Russia envoy