The UK and EU have vowed to “work intensively” to overcome post-Brexit problems in Northern Ireland after border checks on goods were suspended this week.
Talks were held on Wednesday night after checks on goods from Britain to Northern Ireland were suspended over security concerns.
London asked for "rapid action" from the bloc after Prime Minister Boris Johnson criticised its role in the province as it grapples with new trading rules.
The arrangements, known as the Northern Ireland Protocol, avoid the need for a potentially troublesome hard border on the island of Ireland to protect the hard-won peace.
But it means some items arriving from Britain are subject to customs checks as Northern Ireland remains the EU's single market for goods, with Northern Ireland required to apply EU customs rules at its ports.
Checks were suspended this week after port workers carrying out inspections reported threats.
Fears of sectarian tensions were further fuelled over the weekend after the European Commission said it would restrict Covid-19 vaccine exports as the bloc struggles with its supply.
Cabinet Office minister Michael Gove and EU Commission vice-president Maros Sefcovic said in a joint statement they had "concluded that the UK and the EU would immediately work intensively to find solutions to outstanding issues".
They added they had reiterated their commitment to the 1997 Good Friday Agreement that ended three decades of conflict in Northern Ireland, and to the "proper implementation" of its new trade arrangements.
But Northern Ireland First Minister Arlene Foster called for the Northern Ireland Protocol to be scrapped entirely.
She wrote in The Telegraph that extending grace periods for businesses imposed "wholly disproportionate" paperwork on Northern Ireland businesses and the province's links to the UK were at risk. She said the additional checks amounted to "bureaucracy over logic and disruption to supply lines with no actual risk".
Although the EU quickly backtracked on its vaccine proposal following fierce criticism, the threatened move intensified opposition to the new regulations imposed since Britain left the EU's single market and customs union this year.
Earlier on Wednesday, Mr Johnson blamed the aborted EU move for escalating tensions and said he would do everything necessary to ensure Northern Ireland could trade easily with the rest of the UK.
"It was most regrettable that the EU should seem to cast doubt on the Good Friday Agreement, the principles of the peace process, by seeming to call for a border across the island of Ireland," he said.
"We will work to ensure that there are no such borders... and that the principle of unfettered access across all parts of our United Kingdom is upheld."
Mr Johnson added that could include invoking Article 16 of the protocol - the fallback provision the EU briefly triggered Friday, which allows London or Brussels to unilaterally suspend aspects of the deal in special circumstances.
But following Wednesday's meeting, Mr Sefcovic said "flexibilities" agreed within the two sides' Brexit accords should allow any issues to be resolved.
"We should really study how things would look like if the UK would really use and put in practice the flexibilities we agreed," he told Ireland's RTE.
The Northern Ireland Protocol came into effect on January 1, when a Brexit transition period ended and Britain's 2016 vote to split from the EU came into full effect.
It is designed to prevent a hard border emerging between the north and EU member Ireland - a frequent flashpoint in the decades of violence - by transplanting customs checks to Northern Irish ports receiving goods from mainland Britain.
Up to 1998, some 3,500 people were killed as unionists who back ties to Britain engaged in conflict with republicans seeking to merge the province with Ireland.
However, unionist leaders - and more hardcore loyalists sometimes linked to paramilitary groups - oppose the protocol and it has had an uneasy rollout over the past month.
Certifications now required on some food imports such as meat, milk, fish and eggs have caused supply issues, even though supermarkets have been given a three-month grace period before rigorous enforcement begins.
Ahead of talks, Mr Gove sent a letter to his EU counterpart setting out the "rapid action" the UK wants to see.
He urged the EU to take six steps, covering everything from chilled meat rules to pet travel regulations, and included a demand to extend the supermarket grace period until 2023.
"If it is not possible to agree a way forward in the way we propose, then the UK will consider using all instruments at its disposal," he said. "In all cases, what is now required is political, not technical, solutions.”
