Momentum has been building for weeks towards a deal to ease checks on trade that were introduced under the Northern Ireland Protocol - the arrangements agreed to avoid a hard border with EU member Ireland when Britain exited the EU in 2020.

Lawmakers in British Prime Minister Rishi Sunak's Conservative party have been told to be in parliament on Monday, in a sign that a deal could be imminent.

"I think the talks on reforming the protocol are inching towards a conclusion. Certainly the deal isn't done yet, but I do think we are inching towards a conclusion," Leo Varadkar told reporters.

"There is the possibility of agreement in the next few days but by no means guaranteed ... There's still a gap to be closed," Varadkar said, adding there is ongoing engagement between the UK government and European Commission.

Varadkar, who played a key role when the protocol was agreed in 2019, encouraged London, Brussels and Northern Irish politicians "to go the extra mile" to help reach an agreement, saying the benefits would be "huge".

While an agreement would mark an end to a two-year standoff between Britain and the EU, Sunak could face a battle with pro-Brexit Conservative lawmakers and pro-British Northern Irish politicians to make the deal work.

Opinion polls have consistently shown a majority of Northern Irish voters - who opposed Brexit - favour the idea of the protocol, however the province's assembly and power-sharing government have not sat for a year due to unionist opposition.

The Democratic Unionist Party (DUP), the region's largest pro-British party, has said it will not end its boycott of the assembly unless all checks on goods bound for Northern Ireland from Britain are removed.