© AFP/Getty ImagesGraffiti in an area of south Belfast against an Irish sea border.
The Cabinet Office minister, Michael Gove, has asked the EU for an extension to 2023 of the current grace periods for full checks on goods traded between Britain and Northern Ireland.
The bloc's normal rules on customs and product standards are not yet being fully enforced in the Irish Sea but those that are being conducted have led to threatening behaviour towards border officials.
In a letter to the commission's vice president, Maros Sefcovic, the UK government has asked for a series of grace periods, the first of which is due to lapse at the end of March, to be rolled over.
Gove is meeting Sefcovic via video conference on Wednesday after telling parliament that "everything from pet transport to the provision of plants and seeds to gardens in Northern Ireland, and the daily life of our fellow citizens does need to be protected".
Under a protocol in the Brexit withdrawal agreement designed to avoid a hard border on the island of Ireland, Northern Ireland effectively remains in the EU's single market. The full EU customs code is also to be enforced in the Irish Sea on goods coming from the rest of the UK.
On arriving in Downing Street, Boris Johnson had ditched Theresa May's plans to avoid checks by keeping the UK in the EU's customs territory. Johnson claimed that would have prevented the government from reaping rewards of Brexit by striking trade deals with the rest of the world.
The UK government's preferred option for Northern Ireland has been consistently and bitterly opposed, however, by unionists, including the governing DUP, which has said that it will be perceived as a breaking up of the UK.
This week checks on animal and food products arriving into Belfast and Larne ports were suspended amid fears over the safety of staff.
Graffiti has appeared on a wall near the port warning that all border officials are targets. Staff reported that individuals had been spotted taking down their number plate details.
There are concerns that the implementation of further checks required under the withdrawal agreement will only heighten tensions.
Related: DUP launch campaign to scrap Northern Ireland Brexit protocol
Johnson has argued that the EU's ill-fated attempt to trigger article 16 of the Northern Ireland protocol in the withdrawal agreement to erect a vaccine border on the island of Ireland further highlights the need for more flexibility.
The prime minister tweeted on Tuesday evening that there was a need for action from the EU "to preserve the gains of the Belfast Good Friday agreement and ensure that Northern Ireland benefits from Brexit just like every other part of our United Kingdom".
Speaking on Radio 4's Today programme, Ireland's foreign minister, Simon Coveney, counselled that difficulties were inevitable given the type of Brexit chosen by the prime minster.
"Let's not forget that, what is causing all of this tension is Brexit, not the [Northern Ireland] protocol, the protocol is an attempt to try to reduce tension and solve problems linked to Brexit," he said. "There were alternatives to the protocol, which people chose to reject".
Coveney said, however, that the EU and the governments of the UK and Ireland should try and find solutions to defuse tensions at the ports.
He said: "I think, senior political figures need to talk seriously now . trying to defuse tension, which is clearly there, and we need to talk about how we can make the protocol work more effectively and I've spoken to Michael Gove at length, over the weekend in terms of how we might be able to do that, and also his counterpart in the European commission, Maros Sefcovic, and we will work today.
"And also talk to leaders of course in Northern Ireland, about what flexibilities are possible, to try to ensure that the protocol can function in a smoother way than it has today."