THE British government is showing an an "unacceptable trend towards unilateralism" with its Northern Ireland Protocol Bill, the Taoiseach has said.

Micheál Martin spoke in the Dáil yesterday after Westminster MPs voted in favour of the controversial bill to get a second reading on Monday.

The vote means the legislation that seeks to override parts of the UK's 2019 Brexit Withdrawal Agreement with the EU can now proceed to committee stage for further scrutiny.

It is feared that if passed, the bill could spark a trade war between the UK and EU.

Since the publication of the bill to undermine the NI protocol - which places a trade border down the Irish Sea - the EU has launched legal action against the UK.

The EU claims the bill is a "clear breach of international law".

Responding to a question from Sinn Féin president Mary Lou McDonald, Mr Martin said Monday's vote result in London was "regrettable and unacceptable".

He said he had spoken about the result with the President of the European Commission, Ursula von der Leyen.

"This is a trend within the current British government towards aspects of the Good Friday Agreement, be it the protocol, be it legacy issues or be it now, more recently, its action on human rights," Mr Martin told TDs.

"There is an unacceptable trend towards unilateralism. The steps we intend to take is to work absolutely in concert with our European partners."