President Donald Trump has no recollection of meeting with Russian Ambassador Sergey Kislyak at a pre-speech VIP reception at the Mayflower Hotel in Washington last April, AFP reported Tuesday.

The White House has been embroiled in allegations of repeated contacts between members of Trump’s campaign staff and transition team with Russians, which culminated last week in Attorney General Jeff Sessions agreement to recuse himself from any investigation.

The issue, which is under investigation by the House and Senate intelligence committees, has gained traction in the wake of intelligence agency conclusions Russia meddled in the U.S. presidential election by hacking the email accounts of the Democratic National Committee and Clinton campaign chief John Podesta, and planting false news items. The question is whether there was collusion between the Trump campaign and Russian operatives.

The Wall Street Journal reported a few weeks after the encounter Trump greeted Kislyak at a VIP reception last April 27. Three other ambassadors also were on hand.

The reception was hosted by the National Interest, a foreign policy magazine, and Trump stayed for about 5 minutes. Kislyak also attended the speech.

“We have no recollection of who he may have shaken hands with at the reception and we were not responsible for inviting or vetting guests,” White House spokeswoman Sarah Huckabee Sanders told AFP.

Michael Flynn was forced to resign as Trump’s national security adviser last month after misrepresenting his contacts with Kislyak to Vice President Mike Pence. Sessions currently is under pressure because he flatly denied contacts with Kislyak during his confirmation hearing but has since admitted meeting with him twice during the campaign.

Other Trump advisers also have been caught up in the controversy, including former campaign manager Paul Manafort, who was forced to resign, as well as J.D. Gordon and Carter Page. Trump son-in-law Jared Kushner also reportedly had contact with Kislyak.

At a February press conference, Trump denied any contact with Russia.

“I have nothing to do with Russia. Haven’t made a phone call to Russia in years. Don’t speak to people from Russia,” he said, except for the two calls he has received from Russian President Vladimir Putin since the election.