Ségolène Royal has declared her support for Turkey’s bid to join the European Union, becoming the only main contender in France’s forthcoming presidential election to endorse an enlargement deeply unpopular with voters.

“In the end, Turkey has a vocation to join Europe, provided that it satisfies the membership criteria, which are not just economic and financial but also democratic,” the Socialist party candidate said in a new book, extracts of which were published by Le Monde on Sunday.