Unionism could increase its representation from nine to 12 seats in next May's Westminster general election, the DUP deputy leader Nigel Dodds has told his party's annual conference.

The North Belfast MP set the British general election as one of the main themes for the conference by urging unionists to work together to increase representation in the House of Commons after the May poll.

The DUP holds 8 seats while Lady (Sylvia) Hermon is the independent unionist MP for North Down.

"In the 2010 Westminster election, Northern Ireland returned 9 unionist MPs. Northern Ireland could return as many as 11 or 12 unionist MPs to Westminster," Mr Dodds told delegates at the conference, which opened in the La Mon Hotel in east Belfast.

At present the DUP holds just one of Belfast's four Westminster seats, North Belfast, but Mr Dodds contended that apart from the Sinn Féin stronghold of West Belfast, it could take South Belfast from SDLP leader Dr Alasdair McDonnell and the East Belfast seat that DUP leader Peter Robinson lost to Naomi Long of Alliance in 2010.

“A unionist can win in North Belfast, South Belfast and East Belfast. Unionism can take back the capital city of Northern Ireland,” he said.

Mr Dodds criticised Sinn Féin, which has five MPs, for its continued abstentionism from the House of Commons. “Empty seats in Westminster mean no voice for Northern Ireland. Silence won’t stop one cut. Silence won’t deliver one job. Silence won’t put food on anyone’s table,” he said.

Former Belfast lord Mayor Gavin Robinson is the DUP candidate in East Belfast and in emphasising the party's focus on trying to regain that constituency Mr Dodds said that a "lone Alliance voice would be irrelevant".

Mr Dodds also implied that the DUP could have an important role to play in the event of a hung British parliament. “In our national parliament since 2010 the DUP has been the second party of opposition and the fourth largest overall,” he said.

“Anyone who has studied the Westminster scene can have no doubt about the role the DUP has played not just on Northern Ireland matters but in the nation’s affairs over the last five years.”

Mr Dodds criticised the British Labour Party for refusing to back an in or out referendum on the European Union. "It is over 40 years since the last referendum on British membership of the European Union. It is time for the people to decide again. The DUP will continue to be Northern Ireland's strongest advocates for a referendum," he said.

Mr Dodds also praised the Orangemen and loyalists who are continuing to maintain a camp in north Belfast, protesting at the Parades Commission’s decision to ban Orangemen from parading past the Ardoyne shops for the past two Twelfths of July.

He said that through the “darkest days, as we faced the murderous guns of the IRA on one side and the weakness of London on the other” it was a “well of Britishness” that had sustained the union in Northern Ireland.

“It is this well that sustains us still in the united unionist stand of 497 days of peaceful protest at Twaddell in response to intransigent republicanism and a weak Parades Commission. Republicanism will never overcome that power,” Mr Dodds said.