French President Emmanuel Macron has warned Britain again that it cannot maintain full access to the European Union's single market if it doesn't accept the bloc's founding principles, including free movement of people and the jurisdiction of EU courts.

Macron tells the BBC that Britain will undoubtedly negotiate a unique relationship with the EU before it leaves the bloc next year but that any agreement must be consistent with EU rules.

The French leader says "to get full access to the single market you need contribution to the budget and you have to accept ... the four pillars" of EU membership.

The comments undermine the position of some Brexit supporters who want to regain control of U.K. immigration and shun European courts while retaining access to the single market.