The Finnish capital of Helsinki is being considered as a location for a summit between U.S. President Donald Trump and Russian President Vladimir Putin, a senior U.S. official said.

U.S. Secretary of State Mike Pompeo said over the weekend it was likely Trump would meet his Russian counterpart "in the not too distant future" following White House national security adviser John Bolton's visit to Moscow this week.

Russian media quoted the Kremlin as saying last week there were no plans for a meeting with Trump before a NATO summit in Brussels on July 11-12. Trump is expected to attend.