RAMALLAH (Ma'an) -- A constitutional court in Ramallah on Tuesday postponed a hearing on the legality of President Mahmoud Abbas' appointment as prime minister of a unity government to March 20.

Abbas and Hamas chief Khalid Mashaal agreed that the president will lead a unity government in Doha in February.

PLO central council member Abdul-Jawwad Salih submitted a legal challenge to the appointment on the grounds that it is unconstitutional.

Salih's lawyer Raed Abdul-Hamid told the court that chapters 63, 38 and 74 of Article 5 of Palestinian Basic Law defined the explicit distinctions in the roles of prime minister and president in the Palestinian Authority, the official Wafa news reported.

"Chapter 74 defines the prime minister’s responsibilities incontestably," Abdul-Hamid said.

Salih was a member of the first Palestinian Legislative Council and was involved in setting Palestinian basic law.

The head of the Palestinian Higher Judicial Council Farid al-Jallad and justices Sami sarsour, Muhammad Sadr, Eiman Nasser Addin, Imad Salim, Adnan Shuaybi and Khalil Sayyad, are on the jury, Wafa reported. Head of the general prosecution Khalid Awwad also attended the hearing.

Abbas and Mashaal agreed in Doha to form a new government immediately, but the decision to appoint the president and Fatah leader as prime minister caused uproar in Hamas. The new government has yet to be formed.

Abbas told the Qatar-based satellite channel Al Jazeera on Saturday that he agreed on the position on the basis that the government is transitional, technocratic, and has a limited remit of preparing for elections and reconstruction of the Gaza Strip.

If the appointment is illegal he will not retain the role, Abbas added.