BRUSSELS (AP) — The Latest on the European Union summit (all times local):

11:20 a.m.

European Council President Donald Tusk says that he still holds out hope that Brexit can be reversed even though the negotiations on Britain's departure from the European Union officially started this week.

Tusk has made the comments a few hours before a bilateral meeting with British Prime Minister Theresa May. Tusk says that he had been asked by British friends if he could see a way of Britain still staying in.

Tusk said that "I told them that in fact the EU was built on dreams that seemed impossible to achieve."

He added to that by quoting a John Lennon song: "So who knows? You may say I am a dreamer but I'm not the only one."

10 a.m.

European Union leaders are gathering to weigh measures to tackle terrorism, closer defense ties and migration, convinced that anti-EU sentiment and support for populist parties are waning.

Before the two-day meeting in Brussels starting Thursday, summit chairman Donald Tusk trumpeted the resurgence of the EU, even as Britain launched talks this week on leaving.

Tusk told the leaders in an invitation letter that after a series of election defeats for anti-migrant parties, notably in France, the EU is "slowly turning the corner."

He said "we are witnessing the return of the EU rather as a solution, not a problem."

British Prime Minister Theresa May is due to praise the good atmosphere at Monday's Brexit talks, and explain how to protect the rights of citizens hit by Britain's departure.