Muller, 48, announced the decision on Monday following weeks of controversy over the fracas at the downtown Moulin à Dances nightclub, which led an employee of the disco to press assault charges against Muller.

The cabinet minister initially denied striking the bar tender, referring to the incident as a “virile altercation” after the brouhaha came to light several days afterward.

But Muller abruptly settled the affair out of court after being summoned by the canton’s top prosecutor to answer the allegations earlier this month.

The politician, a member of the centre-right Liberal-Radical party, paid the victim an undisclosed sum of money, while apparently acknowledging that he had in fact injured the man.

Muller’s truthfulness about the affair became an issue for the cabinet, which sought to get to the bottom of the case.

The head of the cabinet, Pierre-François Unger, named an expert to determine whether Muller had paid the bar tender a sum of money that would suggest the cabinet minister was in fact guilty of a criminal act.

Eric Stauffer, the head of the Geneva Citizens’ Movement (MCG) party, said the “pay-off” was 50,000 francs ($56,000), a figure that has not been otherwise verified.

Muller told the media on Monday that he had not lied but that the pressure against him had become “intolerable” and that he could no longer continue in his duties.

The construction and information minister was responsible for multi-million-franc projects to expand housing and office space in Geneva, in addition to major public transport investments.

But over the course of his six-year career he has been dogged by scandals.

Muller complained that he had become over the past year a victim of political “harassment” by people intent on harming his reputation.

As an opponent of controlled housing rents, he came under fire for personally benefiting from a reduced rent of 1,800 francs a month for his seven-room apartment in the centre of Geneva – well below the market price.

Muller, trained as a lawyer with a background in the real estate sector, will not leave office without support.

According to cantonal law he is entitled to receive an indemnity of 437,000 francs – 21 times his monthly salary – to help ease the transition away from politics.