UK Prime Minister Theresa May says President Donald Trump advised her to sue the European Union -- rather than go into negotiations with them.

May shared details of their meeting with the BBC's Andrew Marr on Sunday.

"He told me I should sue the EU -- not go into negotiations, sue them. Actually, no, we're going into negotiations with them. But interestingly what the President also said at that press conference was don't walk away -- don't walk away from negotiations, because then you're stuck."

The US President said Friday during a joint news conference with May that he had given the Prime Minister a suggestion that she had found too "brutal."

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