WASHINGTON (Reuters) - The Austrian capital, Vienna, is under consideration as the site of a potential summit between U.S. President Donald Trump and Russian President Vladimir Putin, two sources familiar with the discussions said on Monday.

FILE PHOTO: A combination of file photos showing Russian President Vladimir Putin at the Novo-Ogaryovo state residence outside Moscow, Russia, January 15, 2016 and U.S. President Donald Trump posing for a photo in New York City, U.S., May 17, 2016. REUTERS/Ivan Sekretarev/Pool/Lucas Jackson/File Photos

The meeting could take place in advance of a July 11-12 NATO summit in Brussels that Trump is expected to attend, the sources said. Trump is also expected to visit London for talks with British Prime Minister Theresa May on the trip.

Trump told reporters on Friday that it was possible that he would meet Putin this summer. During a Group of Seven summit in Quebec earlier this month, Trump suggested that Russia be readmitted to the group. The idea met with opposition from some other leaders at the meeting.

Russia was suspended from the group in 2014 for its annexation of Crimea.

“I think it’s better to have Russia in than to have Russia out, because just like North Korea, just like somebody else, it’s much better if we get along with them than if we don’t,” Trump said on Friday.

Trump, who has said he wants better relations with Russia, last met Putin in November in Vietnam on the sidelines of an Asia-Pacific summit.

Trump’s defense secretary, Jim Mattis, was critical of Russia in a speech last week, saying: “Putin seeks to shatter NATO, he aims to diminish the appeal of the Western democratic model and attempts to undermine America’s moral authority.”

NATO was created after World War Two as a bulwark against the former Soviet Union.

A probe of Russia’s alleged involvement in the 2016 U.S. election has hung over Trump’s presidency. U.S. Special Counsel Robert Mueller is investigating whether Trump’s 2016 presidential campaign colluded with Russia.

Moscow denies meddling in the U.S. election and Trump denies any collusion took place.