A Ramallah court on Tuesday postponed a hearing on the legality of Palestinian Authority chairman Mahmoud Abbas' appointment as prime minister of a unity government to March 20.
Abbas and Hamas chief Khaled Mashaal agreed that the PA chairman will lead a Fatah-Hamas unity government in Doha in February.
However, PLO central committee 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 define a separation of powers between the prime minister and president in the PA., 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 aided in drafting the Palestinian Authority's basic laws. .
Abbas and Mashaal agreed in Doha to form a new government immediately, but the decision to appoint the PA chairman and Fatah leader as prime minister caused uproar in Hamas.
Mashaal, who heads the now-itinerant Hamas politburo, has found himself in an imbroglio with his organization's Gaza chief Ismail Haniyeh.
Haniyeh, emboldened by the gains of Islamic parties across the region following the Arab Spring uprisings, has taken a hard-line against any contacts with Israel.
Mashaal, however, has adopted a more moderate approach and endorsed the idea of downshifting to 'popular resistance' in order to obtain a PA state.
Both Mashaal and Haniyeh, however, have echoed Hamas co-founder Mahmoud Zahar's statement that any agreement with Israel will only serve as a "prelude to war."
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 and technocratic. If the appointment is illegal he will not retain the role, Abbas added.
Observers say Salih's case may be moot in light of demands imposed on Mashaal and Abbas by Haniyeh's Gaza faction.
Those demands, which would allow Hamas to effectively retain unilateral control of Gaza while giving it significant influence in PA enclaves in Judea and Samaria, are almost certain to be rejected by Abbas.