BELFAST (Reuters) - British Prime Minister Theresa May must seek fundamental changes to her rejected divorce deal with the European Union, the leader of the small Northern Irish party propping up her minority government said on Tuesday.

“Reassurances, whether in the form of letters or warm words, will not be enough. The Prime Minister must now go back to the European Union and seek fundamental change to the Withdrawal Agreement,” Democratic Unionist Party (DUP) leader Arlene Foster said in a statement.

“We will work with the government constructively to achieve a better deal. That is our focus. Whilst some may wish to use this defeat to boost their political ambitions, we will give the government the space to set out a plan to secure a better deal.”