FILE PHOTO: Britain's Prime Minister Theresa May leaves 10 Downing Street in London, September 6, 2017. REUTERS/Toby Melville/File Photo

LONDON (Reuters) - British Prime Minister Theresa May has spoken with the leaders of Northern Ireland’s two main parties to press them to restore a power-sharing government that collapsed in January.

Northern Ireland’s Democratic Unionist Party (DUP) and its nationalist rivals Sinn Fein have failed so far to agree on how to reform the devolved administration, limiting the province’s influence in Brexit negotiations.

A government spokeswoman said on Wednesday that May had made separate phone calls to DUP leader Arlene Foster and the leader of Sinn Fein in Northern Ireland, Michelle O’Neill, to make clear “the importance of restoring a power-sharing executive to Northern Ireland as soon as possible”.

“They discussed key outstanding issues that remain for both parties and the prime minister encouraged both leaders to come to an agreement soon in the interests of everyone in Northern Ireland.”