U.K. Prime Minister Theresa May faces a daunting array of demands from European Union nations when the time comes to negotiate Britain's relationship with the bloc, an analysis of the 27 other members shows.

The survey — based on responses from ministries, public comments from government officials and interviews with policymakers — reveals European leaders are laying down their own red lines as May's team weighs what it wants to seek in the Brexit talks.

The result is a complex patchwork of priorities — from fishing to shipping, an insistence on freedom of movement to the sovereignty of Gibraltar — that may run counter to what the U.K. wants to achieve and that it will have to seek to satisfy if May is to meet her commitment of making a success of Britain's withdrawal from the EU.