Islamabad, July 21 - The simmering differences between Pakistani President Asif Ali Zardari and Prime Minister Asif Ali Zardari have once again come to the fore with tit-for-tat cancellations by the two leaders and three ministers considered close to the president being threatened with marching orders.

Gilani cast the first round in the current spat by rescinding his one-time mentor Zardari's appointment of Jahanzeb Khan as the ambassador to France, saying he had not been consulted and that the appointment had been made while he was in Sharm el-Sheikh last week for the Non-Aligned Movement summit.

For good measure, Gilani also threatened to sack three ministers close to Zardari, one of whom is believed to be Interior Minister Rehman Malik.

One indication of this was an interview published Monday in which Gilani was quoted as saying: 'Enough is enough. I have assessed the performance of my ministers during the last one year. Now I have to make some changes according to merit, not according to somebody's liking and disliking because I am responsible for running a country of more than 170 million people.'

No names were taken, but the 'somebody' referred to was clearly Zardari.

The other indication was when Gilani stopped the implementation of Malik's order laying down jail terms for Pakistanis sending anti-government - and more importantly, anti-Zardari-e-mails and SMS messages.

'I am not bothered about any e-mail or SMS because nobody is sending anything against me,' the prime minister added for good measure.

'This too is going to be interpreted as an act against the authority of the president because Mr. Malik is known to be Mr. Zardari's protege,' Daily Times noted in an editorial Monday.

Zardari struck back Monday, indicating that he would not agree to Gilani's proposal to appoint administrators in the four provinces in place of the district nazims, who are akin to mayors and are coordinators of cities and towns in Pakistan.

After reviewing the provinces' demand, which was referred to the president by the prime minister, the presidency issued a statement on Monday saying any amendment to the local government system required parliament's approval.