The European Commission on Monday said Britain should put forward a workable solution ahead of next summit of EU leaders with Brexit negotiations at a crucial stage.
The EU said the solution should not be “untried and revocable” arrangements at the Irish border.
The commission spokeswoman, Mina Andreeva, said EU leaders needed time to prepare for the gathering, after several EU leaders urged London to overhaul the proposal by the end of the week.
Britain is due to leave the EU at the end of October, but there is huge uncertainty over the terms of its exit as London is pushing for last-minute changes to the current withdrawal agreement.
British Prime Minister Boris Johnson handed over his idea for an alternative to the backstop, the clause in the exit deal that aims to avoid a hard Irish border – to the EU executive.
Brussels, however, said the suggestions are unacceptable in their current form, while London insists the EU must now meet it halfway and offer concessions in return.
Talks continued on Monday on London’s proposal, with British Brexit Secretary Steve Barclay meeting EU officials in Brussels, although both sides seemed to be digging their heels in.
Britain has made a “big important offer but it’s time for the commission to show a willingness to compromise too’’ a British source in Brussels said.
If not, Britain will leave without a deal, the source added.