The Conservative and Ulster Unionist pairing spent almost twice as much on its disastrous general election campaign than any other party in Northern Ireland.

The £126,500 combined outlay failed to win the Ulster Conservative and Unionist New Force (UCUNF) one seat in the Westminster poll.

The breakdown of the spend showed that David Cameron's party shouldered most of the expense for the failed pact, shelling out just under £110,000 to the Ulster Unionist Party's (UUP) £16,600.

The spend by the UUP was minimal compared to the £251,000 the party stumped up during the pre-UCUNF 2005 campaign. The Conservative Party spent only £8,400 campaigning in Northern Ireland ahead of the poll five years ago.

The figures detailed by the Electoral Commission show that Sinn Fein was the second highest spender in 2010 - with £64,000 invested in its campaign (compared to £44,000 in 2005).

The Democratic Unionist Party (DUP) spent just under £60,000 while the Social Democratic Labour Party's (SDLP) bill was around £52,000. Both the latter parties spent considerably less than they did in 2005, when the DUP invested around £107,000 and the SDLP £154,000.

The Alliance Party's spend of just under £24,000 was slightly up on its £21,100 bill for 2005. Jim Allister's Traditional Unionist Voice spent just over £11,000 in its first Westminster foray.

The overall bill for all main parties that contested the election was well down on 2005. Nine parties reported spending a total of £343,952 on campaigning in Northern Ireland this year, compared to eight parties that spent £596,326 during the regulated period for the 2005 UK general election.

Seamus Magee, head of the Electoral Commission's Northern Ireland office, said: "Voters in Northern Ireland want to know how election campaigners spend their money. We are pleased that in Northern Ireland, all parties submitted their reports on time. This means voters can look at the full picture of how the political parties campaigned for their votes."

Of the total party bill, around £78,000 was spent on party political broadcasts, £135,000 on advertising and £71,000 on leaflets.