President Donald Trump on Friday pledged to adhere to NATO's collective mutual-defense principle after refraining from doing so on a foreign visit to the transatlantic alliance's headquarters.

Axar.az reports citing AA.

"I'm committing the United States to Article Five," Trump said during a joint press conference with Romanian President Klaus Iohannis at the White House. "Certainly we are there to protect, and that's one of the reasons that I want people to make sure we have a very, very strong force by paying the kind of money necessary to have that force."

During a meeting last month at NATO's headquarters in Brussels, Trump omitted the key pledge after claiming the alliance is "obsolete" on the campaign trail, stunning many who expected the announcement.

Trump has continually insisted that NATO members meet a defense spending benchmark of two percent of GDP that they collectively agree to -- a point he made in Brussels.

Currently, only five of the alliance's 28 members have met the two percent goal.

European Commission President Jean-Claude Juncker said on Friday European Union members must increase defense expenditure and protect the bloc.

Juncker said the U.S. was "no longer interested in guaranteeing Europe's security in our place".