Prime Minister David Cameron backs Theresa Villiers over EU referendum stance
Secretary of State rejects calls to quit Northern Ireland role over EU stance
Prime Minister David Cameron has defended Secretary of State Theresa Villiers after she came under fire for saying she will be campaigning for the UK to leave the European Union.
Nationalist and republican politicians in the region questioned Ms Villiers' position in the wake of her decision to back the campaign for the UK to leave the EU.
They have insisted the Conservative MP is not in tune with public opinion in Northern Ireland.
Speaking in the House of Commons, David Cameron - who is campaigning for the UK to remain in the EU - backed his cabinet minister.
"She is exercising her ability to reach a personal decision and to campaign for Britain to leave the EU and that's absolutely right she is able to do that," he said in response to a question from North Antrim MP Ian Paisley.
"I think the key thing is everybody in Northern Ireland should make up their own mind based on the evidence and I look forward to coming to try to help persuade them to remain in a reformed EU."
Sinn Fein Stormont Deputy First Minister Martin McGuinness said Ms Villiers should quit.
However, Ms Villiers herself branded calls for her to resign over her Brexit stance "ludicrous".
"It is clear that a majority of people in the North place great value on our membership of the European Union and want it to continue," he said.
"It's odd that Theresa Villiers should now be advocating withdrawing from the EU when its benefits for the North are quite obvious.
"It's not surprising, however, given the fact that she is not elected by and does not represent the people of the North that she should be so cut off from public opinion."
SDLP leader Colum Eastwood said the Secretary of State should step down if Northern Ireland voted to remain in the EU.
"As I have told her repeatedly, she does not represent Northern Ireland in this position (EU exit)," he said.
"She must not attempt to speak on our behalf."
A spokeswoman for Ms Villiers responded: "The Prime Minister has made clear ministers would be free to campaign in a personal capacity ahead of an EU referendum.
"The Secretary of State remains totally focused on her ongoing and determined efforts to build a brighter, more secure future for NI.
"To suggest otherwise is ludicrous."
In Northern Ireland, Sinn Fein, the SDLP and Alliance Party are all campaigning for the UK to remain within the EU. The Democratic Unionists are backing a Brexit.
The Ulster Unionists have yet to nail their colours to the mast on the issue.