A number of Iranian MPs threatened on Sunday to impeach Foreign Minister Ali Akbar Salehi for appointing a man close to the president\'s underfire chief of staff as one of his deputies. Salehi on Saturday appointed Mohammad Sahrif Malekzadeh as a deputy foreign minister in charge of administrative and financial affairs. Malekzadeh was a top official in the high council of Iranian affairs abroad, run by President Mahmoud Ahmadinejad\'s chief of staff, Esfandiar Rahim Mashaie, whom ultra-conservatives accuse of aiming to undermine the Islamic regime. A number of influential deputies in the conservative-dominated parliament reacted the next day by calling for the impeachment of Salehi. \"We hope that Salehi will sack Malekzadeh as soon as possible ... and rebuff the current of deviation\'s pressure,\" said one of the MPs, Mohammad Dehqan, quoted by Mehr news agency. \"If he does not, the majlis (parliament) will go for impeachment.\" Ultra-conservatives, the Shiite clergy and the elite Revolutionary Guards have repeatedly called for Mashaie\'s dismissal, accusing him of leading \"a current of deviation\" and of exerting too much influence over the president. Ahmadinejad has so far adamantly defended his aides, including Mashaie. The threatened impeachment of Salehi, in a letter posted on the majlis website, said Malekzadeh\'s appointment was against the national interest. \"Such an appointment jeopardises the nation\'s interests ... This person is on the verge of being arrested as (the judiciary) is investigating him over financial and non-financial cases,\" it said. Under the constitution, the signatures of 10 MPs in the 290-seat majlis are needed to start impeachment procedures against an incumbent minister. The move needs the approval of parliament\'s presiding board before being sent for a vote. The rift between Ahmadinejad and ultra-conservatives surfaced in mid-April when he challenged a ruling by Iran\'s supreme leader Ayatollah Ali Khamenei, vetoing a decision by the president to sack Intelligence Minister Heydar Moslehi. Ahmadinejad then withdrew from public life for 10 days, igniting a bitter dispute with the conservatives supporting the supreme leader. Ayatollah Khamenei has since repeatedly called on all factions to rein in their attacks on the president and his aides. The row between the government and parliament has also heightened in recent months over the budget, the scrapping of state subsidies and a project to streamline the cabinet. The parliament is even considering moves to officially question Ahmadinejad, after ultra-conservative lawmaker Ali Motahari said about 90 MPs had signed a petition to do so, according to media reports.