Tory tanks are rolling onto Tom Elliott’s lawn after the UUP leader publicly rejected a proposal to dissolve his party and merge with the Conservatives.

David Cameron has now turned his back on co-operation with the Ulster Unionists and will set up shop in Northern Ireland.

He plans to form a semi-autonomous local party similar to the Scottish and Welsh Tories and fight elections against the UUP.

“The UUP has rejected this opportunity. We think this is a mistake,” Andrew Feldman, joint chairman of the Conservative Party, writes in today’s Telegraph.

Lord Feldman handled much of the talks with Mr Elliott which broke down before Christmas. He added: “The Prime Minister has asked me to continue to move forward in our mission to deliver mainstream, national politics to the people of Northern Ireland, starting in the new year.”

Senior Tory sources in London say they are prepared to plough whatever resources are necessary into the new regional party. Arrangements will be formalised at a meeting of the Conservative Party board later this month.

Lord Feldman was closely involved in negotiations with Mr Elliott at the Conservative conference last October. He rejected the UUP leader’s suggestions for co-operation between the parties as “two-headed” and instead proposed a merger with local Tories. Mr Elliott rejected this offer in a sharply-worded letter on December 21 in which he described local Tories as “an electoral nonentity” which should be wound up.

Last night a senior Tory made it clear that the merger offer was “off the table.”

The source said: “The article you are publishing came out of discussions which Andrew (Feldman) and the Prime Minister had just before Christmas when it became clear Ulster Unionists were not going to accept our offer.”

He added: “If Ulster Unionists for whatever reason, if they had a change of leadership or came to believe they had made the wrong decision, then of course we would put it to the board for a decision.

“As of now the new party is going ahead. We hope to get to the stage where senior figures will be coming over from other parties.”

Euro MEP Jim Nicholson was elected for UCUNF, a previous Tory/UUP partnership now dissolved.

His position was one of number of “technical issues” which the source said would be resolved at a meeting of the Conservative board this month.

He added that the new regional party will have an elected, full-time leader paid by central funds and would be non-sectarian.

“We will make sure it gets what it needs to represent the people of Northern Ireland at the heart of Government,” he said.