The European Union demanded a substantive movement on Tuesday from Britain on fisheries, dispute settlement, and guarantees of fair competition in their talks on a post-Brexit trade deal, with Germany saying they were at a critical stage.
France said the 27-nation bloc must not yield on fishing rights, while Ireland - the EU member most exposed to any abrupt economic split at the end of the year - said Britain was running out of time to seal the terms of a deal.
Britain, the world's sixth-biggest economy, left the EU in January and has since been locked in painstaking talks with the world's largest trading bloc to keep trade flowing freely. A trillion Euros of annual trade are at stake.
EU leaders hold a summit in Brussels on Thursday and Friday to assess progress, and British Prime Minister Boris Johnson has also said he wants to know by Oct 15 if a deal can be reached.
The European affairs minister of Germany - current holder of the bloc's rotating presidency - said the EU was working hard for a deal but was ready if necessary to trade from 2021 without an accord.
We are at a very critical stage in the negotiations and we are extremely under pressure, Michael Roth told his 26 fellow ministers. In terms of substance we have not really made progress.
We expect substantial progress by our friends in the United Kingdom in key areas: in particular on governance, 'level playing field' and fisheries.
Roth said the EU would step up contingency planning in case of failure in the negotiations on a new partnership - which is meant to cover many areas from trade to transport and nuclear ties - from Jan 1, when London's post-Brexit standstill transition ends.
Johnson, a key face of the 2016 Brexit campaign, has spoken with French President Emmanuel Macron and German Chancellor Angela Merkel in recent days, and was due to speak on Wednesday with the head of the EU's executive, Ursula von der Leyen.
On Tuesday, Merkel said a deal was in the interests of all but also flagged the need to prepare for a no-deal outcome.