BERLIN/PARIS, July 2 (Reuters) - NATO plans to replace its aging fleet of U.S.-made AWACS surveillance aircraft with Swedish alternatives, four sources told Reuters, a move that could anger President Donald Trump, who has urged allies to buy more U.S. equipment.

Trump has repeatedly criticized European allies for relying on the United States for their security, while pressuring them to increase defense spending and purchase more American equipment. He has also threatened on occasion to withdraw Washington from NATO.

The sources said the purchase of the Saab Global Eye surveillance aircraft will be announced at the NATO summit in Ankara from July 7-8.

A NATO spokesperson confirmed that a decision regarding the replacement of the AWACS aircraft would be announced during the summit, but declined to provide details. Saab declined to comment.

The anticipated announcement from NATO comes weeks after Canada announced plans to purchase six Global Eye aircraft, its largest order for the aircraft to date, as it seeks to reduce its reliance on American defense suppliers.