The BBC’s Laura Kuenssberg said the trip did not guarantee there is a new deal to be signed by both sides.
But she said sources told her they believe direct talks are the right way to progress at this critical moment.
The EU has said it is now up to MPs to decide the next steps for Brexit and it remains “committed” to agreeing a deal.
But earlier in the Commons, Labour leader Jeremy Corbyn said there had “not been a single change” to the agreement since it was heavily defeated by MPs in January and it was still a “bad deal”.
Following speculation the vote could be postponed or downgraded, No 10 said the motion to be debated would be published later on Monday – although it gave no details of what it could contain.
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Downing Street said the PM’s focus was “getting on with the work required to allow MPs to support the deal and to bring this stage of the process to an end”…
At the eleventh hour, Theresa May claims to have made a breakthrough in Brexit negotiations.