President Donald Trump is expected to provide written answers to questions from the special counsel investigating Russian interference in the 2016 U.S. presidential election as soon as this week, a person familiar with the matter said on Tuesday.

The questions from special counsel Robert Mueller that Trump is preparing to answer relate only to Moscow's involvement in the election, and not to whether Trump may have tried to obstruct the Russia investigation, the source told Reuters.

Among the topics covered is a June 2016 meeting between the president's son, Donald Trump Jr., other members of Trump's campaign team and a group of Russians, the source said.