There has been intense inter-unionist rancour recently but the First Minister said that the 2012 anniversary was a perfect opportunity for unionists to come together to celebrate a defining moment in twentieth century unionism.

Mr Robinson said that he would be writing to Sir Reg to "establish a joint working group between the two parties to organise a series of events and commemorations around the anniversary" of the Ulster Solemn League and Covenant, when 471,414 Ulstermen and women, headed by Lord Carson, signed to show their opposition to Home Rule.

The East Belfast MP said: "I believe that such an anniversary belongs to everyone in the unionist community and that the unionist parties should co-operate in organising a series of events to commemorate this special and significant anniversary.

"I will therefore be writing to Reg Empey to seek out ways in which both unionist parties can work together to jointly organise a series of events to celebrate this important date in unionist history. I hope to see a working group formed to that effect.

"The DUP is determined that this anniversary will not go unmarked and we are committed to ensuring it receives the attention that it deserves.

"I hope that Reg Empey will respond positively to this initiative and that all unionists will work to mark this vital date in the manner it deserves."

However, Sir Reg Empey told the News Letter that his party had last year set up a group to look at commemorating the centenary.

He said that UUP chairman David Campbell, along with former Belfast Lord Mayor, historian Ian Adamson and others, were involved in the committee.

"We have been working on it for some considerable time and it's something which is out there and people know about," he said.

"I have myself attended several meetings in recent weeks with other interested groups about the issue.

"The Ulster Unionist Council was very much involved in the covenant and indeed largely organised it so I think that all unionists - of every persuasion - will take interest in such an anniversary."

Mr Robinson said that while Home Rule never came to pass, it was only the "determined efforts of Carson and Craigavon which kept this part of the island out of the Irish Free State and led to the foundation of Northern Ireland".

"The starting point for such a state-of-affairs coming to pass was 1912 – with the Solemn League and Covenant and the formation of the Ulster Volunteers.

Mr Robinson's statement made no mention of a representative from Traditional Unionist Voice being invited to join the group.