Former Northern Ireland first minister Lord Trimble is threatening to take the government to court over the controversial Brexit backstop.
Lord Trimble said that he and others are planning to initiate judicial review proceedings over an alleged breach of the Good Friday Agreement.
The former leader of the Ulster Unionist Party - currently sitting in the House of Lords as a Conservative peer - said the proceedings would demand the removal of the protocol on Northern Ireland from Prime Minister Theresa May's Withdrawal Agreement.
He said that the backstop should be replaced by alternative arrangements set out in a report entitled ‘A Better Deal and A Better Future’ authored by Eurosceptic Conservative MP Steve Baker and published by the Global Britain group.
A spokesman for Lord Trimble was unable immediately to provide an explanation for the claim that the protocol breaches the Good Friday Agreement.
The former UUP leader was awarded the Nobel Peace Prize for his part in the negotiations leading to the 1998 Agreement which provided the framework for a return to peace in Northern Ireland following the Troubles.
EU negotiators have argued that, until a broader trade deal is in place, the backstop is essential to safeguard the Good Friday Agreement by preventing the creation of a hard border on the island of Ireland.