Tehran: The mayor of Iran's capital Tehran resigned after hard-liners criticised him for attending a ceremony in which primary school girls danced, Iranian media reported today.

Mohammad Ali Najafi submitted his resignation to Tehran's City Council and the council was expected to discuss over this issue in April.

Last week, prosecutors summoned Najafi for attending the ceremony in which a group of under-age girls danced in a ceremony held to commemorate International Women's Day.

Council head Mohsen Hashemi Rafsanjani, without elaboration, said Najafi resigned due to illness.

Hard-liners used the case to increase pressure on the US-educated 65-year-old technocrat who came into office in August promising to fight corruption.

Official reports say the municipality had some USD 10 billion in debt, including USD 1 billion to contractors, when Najafi took office.

Najafi had taken over from Mohammd Bagher Qalibaf, a conservative politician who briefly stood as a candidate against President Hassan Rouhani in May before dropping out.

Mohammad Reza Aref, a reformist parliament member and former vice president under President Khatami, asked the City Council to review Najafi's resignation and change his decision.

Reformists believe that pressure has been placed on Najafi following his claims of fraud in Tehran's municipal government during Qalibaf's time as mayor.

Parliament member Parvaneh Mafi was quoted by the Hamshahri daily as saying Najafi's "efforts to combat corruption ... may have led to pressures on him and affected his resignation."

Political pressures on Najafi are the result of factional push and pull between hard-liners and moderate President Hassan Rouhani's administration.

Iranian hard-liners in Parliament this week tried to impeach three of Rouhani's ministers, but failed.