BRUSSELS (AP) — Donald Tusk, the president of the European Council, says the European Union has agreed on guidelines that will govern upcoming discussions over its future relations and trade links with Britain after Brexit next year.

Tusk tweeted during a summit in Brussels Friday that the guidelines will steer "future EU-U.K. relations."

The document lays out the approach Britain's 27 EU partners will take on a variety of matters, including future security, defense and foreign policy ties, as well as the outlines of a future trade deal.

Britain is permitted to negotiate trade agreements after it official leaves the bloc at midnight on March 29, 2019, but no pact can enter force without EU permission before the end of December 2020 after a post-Brexit transition period.