Advisers to President Trump's 2016 presidential campaign were in contact at least 18 different times with Russian officials or other people with ties to the Russian government during the election race, according to Reuters.

These communications were previously undisclosed, and took place between April and November 2016, the report said. Current and former officials familiar with the calls and emails told Reuters that six of the contacts were phone calls between former National Security Adviser Michael Flynn and Russia's ambassador to the U.S., Sergey Kislyak. The report added that conversations between Flynn and Kislyak accelerated after the November election.

Besides the six phone calls involving Flynn, the 12 other contacts were calls, emails and text messages between Trump campaign advisers and Russian officials, or people believed to be close to Russian President Vladimir Putin.

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No evidence of wrongdoing or collusion emerged in the communications, the officials told Reuters, but they are part of the record the FBI and congressional investigators are examining, the report said, as part of the federal probes into Russian interference in the U.S. election.

The White House denied contact with Russian officials during the campaign in January, the report notes. At the time, Vice President-elect Mike Pence told CBS's "Face the Nation" that there was no contact between the Trump team and Russian officials during the election campaign.

"Of course not," Pence said when asked whether anyone from the campaign was ever in touch with Russia. "I think to suggest that is to give credence to some of these bizarre rumors that have swirled around the candidacy."

In that same interview, Pence said that Flynn's conversations with Kislyak during the transition "had nothing whatsoever to do with [U.S.] sanctions (against Russia)," a statement that later turned out to be false, and which cost Flynn his job.

This comes after The New York Times reported Wednesday night that Flynn told the Trump transition team ahead of inauguration that he was under federal investigation for secretly working as a paid lobbyist for Turkey during the campaign.