The U.K. and EU chief Brexit negotiators are in self-isolation Friday as a result of the coronavirus outbreak, throwing the timeline of Brexit talks into doubt.

David Frost, 55, is in self-isolation after showing symptoms of coronavirus, according to a British official.

And the EU’s Michel Barnier, 69, announced Thursday that he had tested positive for the virus.

The two top officials met for the first round of talks in Brussels two weeks ago, but have not had contact since.

“I would like to inform you that I have tested positive for #COVID19. I am doing well and in

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