The position was agreed without dissent following a near three-hour debate at the parliament buildings in Stormont.

It was one of the first substantive acts of business since the assembly was restored earlier this month following the power-sharing deal.

Its two largest parties are the DUP and Sinn Fein, who oppose the Prime Minister's Brexit deal for different reasons.

Northern Ireland has been unable to speak without the authority of elected ministers throughout most of the debate over Brexit due to the three-year suspension of the devolved institutions.

Northern Ireland voted in favour of Remain in the 2016 EU referendum, but there was a significant body of mainly-unionist opinion in favour of Leave.

The DUP is largely pro-Brexit, but opposes Prime Minister Boris Johnson's plan over fears it could impose customs checks on goods travelling between England, Scotland or Wales and Northern Ireland.

There have been fears leaving the EU could encourage dissident republican violence or re-open the debate over Irish unity, since the Republic of Ireland remains a member state.

Later in London, Johnson's government was defeated in the UK parliament for the first time since the December general election, with the upper chamber voting in favour of a move to protect the rights of EU citizens in Britain after Brexit.

Brexit legislation is now passing through the House of Lords, where the government does not have a majority. And while the upper chamber is not expected to block passage of the bill, it is seeking to make changes.

Members of the Lords voted by 270 to 229 in favour of a change put forward by the pro-EU Liberal Democrats which would give eligible EU citizens in Britain an automatic right to stay, rather than having to apply to the government to do so.

It would also ensure they are given physical proof of their right to remain. The government has said only that people will be given a "secure digital status" which links to their passport.

Meanwhile, Britain's trade talks with the EU may not begin until March, Brussels has admitted as Downing Street insisted the UK was ready to start negotiating on February 1.

The European Commission said it would "take some time" for the bloc to agree its position despite PM Johnson has repeatedly insisting that a deal must be reached by the end of December.

European Commission spokesman Eric Mamer said the process of agreeing the EU's position could only begin after Brexit.

"This, we know, will take some time, which is why we have said we will start negotiations as quickly as we can, but it will certainly not be before the end of February, beginning of March," he said.

Australian Associated Press