Ghana's opposition MPs on Thursday walked out of Parliament as President John Mahama arrived to present his state of the nation's address protesting the outcome of last year's elections.

The MPs who backtracked from a New Patriotic Party earlier caucus decision to attend the session waved placards written "thieves."

They vowed to continue boycotting functions where Mahama would be officiating.

NPP legislators also stayed away from the president's inauguration on January 7.

The party refused to participate in the vetting of ministerial nominees arguing the appointments would be reversed if their court case challenging the outcome of the December 2012 polls succeeds.

NPP petition the Supreme Court challenging the election results and a ruling is yet to be made.

The party's candidate in the presidential elections Nana Akufo Addo and his running-mate Mahamadu Bawumia in their court application claimed the polls were marred by several irregularities.