Iran today said it has reservations on the appointment of Pakistan's former army chief Gen Raheel Sharif as the head of the Saudi-led 39-nation Islamic military alliance, warning that it may "impact" the unity among Muslim countries.<br/>'<br/>Iran's state-run IRNA news agency quoted the country's Ambassador to Pakistan Mehdi Honardoost as saying that Tehran had conveyed its concerns to Islamabad.<br/><br/>He said Tehran had informed Islamabad that Iran would not become part of such a military alliance, adding that neither had Iran been extended an offer to join a coalition of this sort.<br/>'<br/>Gen Sharif, who retired as army chief last November, is likely to assume command of the anti-terrorism alliance, being dubbed the 'Muslim Nato', this month.