Islamabad, Jun 22 (IANS): Raja Pervez Ashraf was Friday officially declared as the joint candidate for the post of Pakistan's prime minister by the Pakistan Peoples Party (PPP) and its allies, Muttahida Qaumi Movement (MQM), Awami National Party (ANP) and Pakistan Muslim League-Quaid (PML-Q).

The announcement was made by PPP's Khursheed Shah, Haider Abbas Rizvi of the MQM and Afrasiab Khattak of the ANP, Dawn News reported.

On Thursday night, the coalition partners, at a meeting chaired by President Asif Ali Zardari, authorised the PPP to name the next prime ministerial candidate, Geo News said.

During the meeting attended by leaders of the PML-Q, the MQM and the ANP, the allies unanimously approved the name of Ashraf for the post, presidential spokesman Farhatullah Babar said.

A special session of the National Assembly has been summoned Friday evening to elect the new prime minister, after Yousuf Raza Gilani was disqualified by the Supreme Court. Speaker Fehmida Mirza will chair the proceedings.

Two opposition candidates, Maulana Fazlur Rehman from the Jamiat Ulema-e-Islam-Fazl (JUI-F) and Sardar Mehtab Abbasi from the Pakistan Muslim League-Nawaz (PML-N), had filed nomination papers Thursday.

Tipped earlier as a covering candidate, Ashraf was Thursday named the party's main candidate for the office of prime minister following the issue of a non-bailable arrest warrant against the previous contender Makhdoom Shahabuddin.

Shahabuddin's name was dropped after an anti-narcotics court Thursday issued a non-bailable arrest warrant against him as well as disqualified prime minister Yousuf Raza Gilani's son Ali Musa in an illegal drugs quota case, Geo News reported.