The EU and UK say there is a "new basis" for resolving the Northern Ireland Protocol row after an agreement was reached on sharing trade data.
Foreign Secretary James Cleverly and Northern Ireland Secretary Chris Heaton-Harris met EU chief negotiator Maros Sefcovic in London on Monday, as efforts to find a way forward over post-Brexit arrangements in the region continue.
The agreement will allow the EU to access UK IT systems which will provide detailed information about goods flowing from Great Britain to Northern Ireland.
Both sides hailed an agreement as a key step in resolving the deadlock over the protocol, which has left Northern Ireland without a devolved powersharing executive since early last year.
But David Lammy, Labour's shadow foreign secretary, said: "Three years after we left the EU, the government's progress on fixing the Protocol it negotiated is pathetic. A working data arrangement with the EU is of course welcome, but just one aspect and long overdue."
The protocol has overshadowed Northern Irish politics since it was agreed as part of the Brexit deal in a bid to avoid a hard border on the island of Ireland.
Members of the unionist community are unhappy with the difficulties it creates for trade between Northern Ireland and Great Britain, with the Democratic Unionist Party (DUP) refusing to co-operate with forming a devolved Executive in Stormont until the issues are resolved.
The UK government says the protocol is not working and wants to override it with new legislation if the EU does not agree to changes - a move Brussels has warned is "illegal and unrealistic".
However, tensions have cooled in recent months, with both sides pledging to work together to find a way forward.
Meeting 'cordial and constructive'
A joint statement, issued after the meeting on Monday, described it as "cordial and constructive".
It said the data-sharing deal "was a critical prerequisite to building trust and providing assurance, and provided a new basis for EU-UK discussions".
The statement said that officials in London and Brussels would now "work rapidly to scope the potential for solutions in different areas on the basis of this renewed understanding".
Mr Sefcovic also called it a "new basis" for UK-EU discussions - a sentiment echoed by Ireland's foreign affairs minister Micheal Martin.
However, the prime minister's official spokesman stressed: "There are still significant issues at the heart of the protocol that need addressing."
An unofficial deadline for an agreement - and the possible resumption of the Stormont power-sharing government - is 10 April, the 25th anniversary of the Good Friday Agreement that brought peace to Northern Ireland, and a potential visit from US President Joe Biden.