At his campaign rally, in a packed hall where people waved French and EU flags, Macron drew the biggest cheers when he spoke in favour of the European project.

"Our country cannot succeed without Europe," he said.

He advocated a "special relationship" between the EU and France on the one hand and Britain on the other. The term is more commonly used in Britain to describe ties with the United States.

"Nothing will be the same (after Brexit), but I think we can defend mutual interests over the long term," he said, citing close cooperation between London and Paris on defence and security.

He suggested he would seek to partially renegotiate the Le Touquet agreement, which allows France and Britain to have border controls on each other's territory, so that London would contribute more to managing the issue of refugees and migrants who gather in Calais in northern France to seek ways to Britain.

Macron said he and May had discussed what would happen to French expatriates in London after Brexit. He said he wanted them to be free to continue their lives in Britain if they so wished.

But he also said that he was fed up with hearing about young French entrepreneurs who felt they could not succeed in France and moved to London because it was easier to start a business there. He said his ambition as president was to make France more attractive so such people would stay, or return.