"The present government... is afflicted by a great scourge and has been infiltrated by corrupt elements," Hodjatoleslam Ali Saidi was quoted by Mehr news agency as saying.
He appeared to be referring to President Mahmoud Ahmedinejad's chief of staff and closest aide Esfandiar Rahim Mashaie, who for the past month has been subject to personal criticism from religious conservatives.
Mashaie has been accused of "bewitching" the president with magic spells, of having too much influence over him and of leading a "current of deviation" aimed at destroying the Islamic regime.
Saidi accused Ahmadinejad of circumventing the will of the supreme leader, who in July 2009 rejected Mashaie's nomination as first vice president, by giving him "greater power in reality" as chief of staff.
He also criticised anew the president's boycott of his official duties in late April in protest at Ayatollah Khamenei's veto of Ahmedinejad's sacking of Intelligence Minister Heydar Moslehi.
"The people and the clerics expect Ahmadinejad to show his loyalty to the supreme leader, to accept body and soul his will, and not to sulk and stay at home," Saidi said in reference to the president's 10-day withdrawal from public life in protest at the Ayatollah's decision to retain Moslehi.
"I hope that Ahmadinejad will return to the right path," Saidi added.
He also asked the president and his government do not intervene in next March's parliamentary elections, in which the president's camp has not hidden its intention to put forward its own candidates to run against the present conservative majority.
"The officials charged with supervising the elections must ensure... that the government does not intervene in the electoral process," Saidi said.
He also reprised his accusations that elements within the president's entourage are engaged in occult practices, a charge levelled by religious ultra-conservatives since the start of the crisis between the president and the Supreme Leader.
"Certain individuals" within government have used "satanic methods" such as "bewitchment and sorcery, which are 'haram,'" or forbidden in Islam, he said.