LUXEMBOURG (AP) -- European Union and British foreign ministers expressed cautious optimism Monday that a deal on Britain's departure from the bloc will be found soon but virtually ruled out any agreement at a crunch summit this week.
Talks between the two sides on Sunday failed to bridge important gaps, notably on how to keep goods flowing freely between EU member state Ireland and Northern Ireland, which is in the U.K., after Britain leaves.
Britain officially exits the EU on March 29, but a deal must be clinched in coming weeks to allow time for the EU and U.K. parliaments to ratify it. No new meetings between ambassadors are scheduled before EU presidents and prime ministers meet in Brussels on Wednesday.
"There are one or two very difficult outstanding issues, but I think we can get there," British Foreign Secretary Jeremy Hunt told reporters in Luxembourg where EU foreign ministers are meeting. "Whether we do this week or not, who knows?"
"Everyone is trying incredibly hard. I think it is possible to do it and I think with goodwill on both sides we can get there," he said.
Irish Foreign Minister Simon Coveney admitted to being "frustrated" by the delay, saying that apart from Britain, Ireland is the country with most to lose from Brexit.
Coveney suggested that Prime Minister Theresa May's British government is reneging on part of its commitment to ensure that no "hard border" involving lengthy customs checks and controls emerges on the Irish border.
He said that Britain agreed in December and again in March that the unpopular "backstop" guarantee would remain in place until a better solution is found, but now appears to only want it used for a limited time.
"A backstop cannot be time limited. That's new. It hasn't been there before," he said. "Nobody wants to ever trigger the backstop, but it needs to be there as an insurance mechanism to calm nerves that we're not going to see physical border infrastructure re-emerging."
A hard border between the two could revive tensions between Northern Ireland's pro-Irish Catholic and pro-U.K. Protestant communities. More than 3,700 people died over 30 years of "troubles" and the communities have not yet buried their differences.
Like Britain's Hunt, Spanish Foreign Minister Josep Borrell said "it seems that this week it will not be possible, but this week is not the end."
"We will keep negotiating," Borrell said. "It is difficult for me to believe that we will not be able to reach an agreement."
He said that he foresees no problems between Britain and Spain over Gibraltar.
"It's not a rock in the way," Borrell said, referring to the nickname of the territory bordering Spain. He added that the Irish border problem is "more difficult to solve than Gibraltar."
Slovak Foreign Minister Miroslav Lajcak said: "There is no reason to panic. There is still time."
May is under intense pressure from her Conservative Party and its parliamentary allies not to give any more ground in negotiations, especially on the border issue.
The lack of a breakthrough on the border increased the chances that the Brexit negotiations will fail to produce an agreement spelling out how the EU will interact with its former member and vice versa. EU officials had warned that real progress was needed at this week's summit.
May's political allies, the Democratic Unionist Party, stand ready to scuttle a divorce deal over the border issue. The party opposes any border customs checks but EU officials say that may be the only way to avoid a hard border.
DUP Brexit spokesman Sammy Wilson said "it is probably inevitable that we will end up with a no-deal scenario" because there was no agreement that would be accepted by Britain's Parliament.
International Development Secretary Penny Mordaunt said Monday that "everyone needs to calm down" and support May as she tries to get a deal with the EU.
In Luxembourg, German Foreign Minister Heiko Maas said he hopes "that in the end good sense will win the upper hand."
"Time is really pressing now," Maas warned.