British Brexit minister David Frost said on Wednesday that there was more work to be done in negotiations with the European Union over post-Brexit trade with Northern Ireland and he was not ready to give up yet.
Britain has repeatedly warned that it may trigger emergency measures called Article 16 which allows either side to take unilateral action if they deem their agreement governing post-Brexit trade is having a strongly negative impact on their interests.
"This process of negotiations has not reached its end, although we have been talking for nearly four weeks now there remain possibilities that the talks have not yet seriously examined," Frost told parliament's upper chamber.
"There is more to do and I certainly will not give up on this process, unless and until, it is abundantly clear that nothing more can be done. We are certainly not at that point yet."
The gap between the EU and Britain has narrowed but remains extremely wide, he said.
Article 16: 'Not Inevitable But May Be Britain's Only Option'
Frost, who is due to hold further talks with the European Commission's Maros Sefcovic on Friday, said triggering Article 16 was not inevitable but may be Britain's only option.
Irish Foreign Minister Simon Coveney has suggested that triggering Article 16 would mean the 2020 trade deal would have to be set aside.
But Frost said using such safeguards would be entirely legitimate and that threats over what the EU might do if Britain triggers Article 16 were unhelpful.
"They (the EU) are also suggesting that we can only take that action at the price of massive and disproportionate retaliation," he said. "I gently suggest that our European friends should stay calm and keep things in proportion."
On Tuesday, Irish government ministers met to dust off contingency plans in case disagreements between Britain and the European Union triggered major trade disruption, deputy prime minister Leo Varadkar said.