France and Britain on Thursday agreed to reinforce cooperation over their respective nuclear arsenals as the two European powerhouses seek to respond to growing threats to the continent and uncertainty over their U.

At a summit on Thursday, Prime Minister Keir Starmer and President Emmanuel Macron also announced a “one in, one out” pilot program on migrants crossing the English Channel.

French President Emmanuel Macron on Tuesday urged Britain to stick close to its neighbors despite its exit from the European Union, saying France and the U.K. will “save Europe” by standing for democracy,