ISLAMABAD - Prime Minister Yousuf Raza Ginlani has, apparently, been operating as a docile chief executive under overwhelming umbrella of President Asif Ali Zardari, whereas things are not that smooth between the two, TheNation has learnt. According to sources privy to the two top offices of the PPP regime namely the Presidency, and the Prime Minister House, differences between Zardari and Gilani have emerged out of the clash of choice. As a result of the covert friction between the President and the Prime Minister, the latter has been left without a full-fledged Principal Secretary, Siraj Shamsuddin, who had sought a better job with the Asian Development Bank for some obvious reasons leaving his boss in the lurch, the sources said. Although the Establishment Division has notified the posting of Nargis Sethi, a senior DMG official at the PM Secretariat as the officiating PSPM, no one had so far been designated as full-fledged PSPM, sources in the Division confirmed. The sources further revealed that the Prime Minister had not yet conveyed his desire to have one bureaucrat as chief of his staff. The sources claimed that the person whom the PM wanted as his Principal Secretary was not getting clearance from the Presidency. According to the sources, the Prime Minister had also been uneasy with the President jumping in to head various meetings of the government besides passing on direct instructions to some of the top bureaucrats mostly from District Management Group. Moreover, the sources also revealed differences between the President and the Prime Minister over the critical issue of National Finance Commission, which the former regime of General Pervez Musharraf, too, had held in abeyance by replacing it with a self-styled formula. According to the sources, the President wanted PM's Advisor on Finance Shaukat Tarin to head the NFC, who, not being a parliamentarian, could not hold the position under the Constitution. Although Tarin was on record having said that he could not chair the NFC for being an Advisor, and therefore the Prime Minister would chair it, the sources ruled out likelihood of Premier Gilani doing so in the near future. The sources were of the view that the President was not happy with the Prime Minister Gilani chairing the NFC. "Thus Zardari wanted to make Tarin as Finance Minister after getting him elected as Senator during the upcoming Senate elections in March 2009 so that he could qualify to chair the NFC under the Constitution," the sources maintained. According to the sources, Zardari was also not satisfied with the way Prime Minister Gilani handled the Indian complaints with regard to Mumbai incident while talking to his counterpart Manmohan Singh. The sources confided to TheNation that the President undermined Prime Minister's statutes on certain occasions. To mention one such instance, they said, the President overdid while inviting British Prime Minister Gordon Brown to the Presidency for lunch that was the prerogative of the visiting guest's counterpart. "So much so, the President summoned the Prime Minister to join his lunch with the visiting Premier which Gilani regretted as perhaps the first expression of asserting his position," the sources said. "That is why, the British Premier had to call on the Prime Minister out of mere courtesy even after addressing a joint press conference with President Zardari," the sources added.