Theresa Villiers new Secretary of State for Northern Ireland

Mr Paterson, who has been coming to Northern Ireland for five years since being appointed shadow secretary of state in July 2007, has moved to the Department for the Environment, Food and Rural Affairs. He will now have responsibility for government policy on controversial issues such as shale gas and a cull of badgers.

Mr Paterson’s junior minister, Hugo Swire, has also been promoted, moving to become Foreign Secretary William Hague’s number two.

Ms Villiers, who at 44 is one of the youngest members of Cabinet, last night said that she was “delighted” to have been given the job.

She paid tribute to Mr Paterson, describing him as “my distinguished predecessor”, and said that “his commitment and hard work on behalf of the people of Northern Ireland were widely acknowledged”.

The Oxford-educated barrister is a former MEP for London and was known at the European Parliament for her Eurosceptic views, something which she shares with Mr Paterson.

Ms Villiers entered the Commons in 2005 as MP for Chipping Barnet on the edge of north London and served as shadow chief secretary to the Treasury and shadow transport secretary before entering government as minister of state for transport when the Coalition Government was formed.

Ms Villiers’ appointment reinforces the Prime Minister’s public commitment before the last General Election to maintaining the separate roles of secretary of state for Northern Ireland, Scotland and Wales.

In May, Deputy First Minister Martin McGuinness called for the abolition of the role. However, several Conservatives have argued that it maintains an important link to the Cabinet for Belfast, Cardiff and Edinburgh.

In a statement, Ms Villiers, who is Northern Ireland’s first female secretary of state since Mo Mowlam, said: “Huge progress has been made in Northern Ireland over recent years. As the headlines in the past few days demonstrate, however, we still have some way to go if we are to overcome the divisions in society and build a genuinely shared future.”

She added: “I am acutely conscious of the need to continue our efforts to rebalance the Northern Ireland economy. In addition the Government will maintain the utmost pressure on those who resort to terrorism and violence to pursue their objectives.”

Both the DUP and Sinn Fein have had increasingly strained relations with Mr Paterson and his criticisms of the Stormont Executive.

First Minister Peter Robinson issued a brief statement asking for a meeting with Ms Villiers “as soon as possible”.

The DUP leader said: “I look forward to working with Theresa on a wide range of outstanding issues which require her urgent attention.

“I thank Owen for his efforts as secretary of state for Northern Ireland over the past five years and wish him every success in his new post as secretary of state for environment.”

Sinn Fein president Gerry Adams said: “I wish Owen Paterson well in his new job,” but quickly added: “However, I hope that his successor Theresa Villiers will bring a new and more progressive focus to the many issues which need to be dealt with at this time.”

Ulster Unionist leader Mike Nesbitt, whose party had until last year a link with the Conservatives, paid “warm tribute” to Mr Paterson’s role in Northern Ireland.

Mr Nesbitt said that the outgoing secretary of state had been “hard working” and, prior to taking up that position, “possibly the most diligent shadow secretary of state we have ever had”.

“I hope his successor will show the same enthusiasm and commitment,” said the UUP chief.

Mr Nesbitt said that he wanted to clarify whether Ms Villers will support the devolution of corporation tax, an issue championed by Mr Paterson.

TUV leader Jim Allister said that he had known Ms Villiers when they were both MEPs. He described her as a “very able lady”.

SDLP leader Alasdair McDonnell congratulated Mr Paterson on his promotion and added: “We agreed on some issues and disagreed on many. One thing we did agree on was to reduce corporation tax.”