Then-Palestinian Finance Minister Salam Fayad, center, former government General Secretary Hasan Abu-Lebdeh, right, and former Labor Minister Ghassan Khatib sit in an office in the West Bank city of Ramallah in 2003. (Muhammed Muheisen/Associated Press)

Since signing a reconciliation accord more than a month ago, the Palestinian factions Fatah and Hamas have made only slow progress in carrying it out, and on Sunday the pact hit its first significant snag with a public disagreement over who should be prime minister of a joint government.

The dispute over Fatah’s nomination Saturday of Salam Fayyad, a political independent who is the Palestinian Authority premier, cast a shadow over planned talks in Cairo on Tuesday on the composition of the new cabinet.

The candidacy of Fayyad is key to whether a unified Palestinian government will continue to have the Western backing that the Palestinian Authority has received during his term in office. The U.S.-educated economist is respected by foreign donors and has been credited internationally with revamping Palestinian finances and building government institutions necessary for statehood.

The United States, Israel and the European Union classify Hamas as a terrorist organization and demand that any Palestinian government backed by the group renounce violence, recognize Israel and accept previous Palestinian-Israeli accords. Fayyad’s appointment as prime minister would help allay donor concerns that foreign aid might end up in the hands of Hamas.

Under last month’s accord, which ended a four-year rift, Fatah and Hamas agreed to form a government of unaffiliated technocrats whose chief task would be to prepare for presidential and parliamentary elections in a year.

But influential Hamas officials in the Gaza Strip balked Sunday at Fatah’s nomination of Fayyad, whose policies are seen by the Islamist group as aligned with U.S. interests in the region.

“Salam Fayyad is unacceptable, because he has drowned the Palestinian people in billions of dollars of debt and made its economy and political decision-making dependent on foreign donors,” Salah Bardawil, a member of the political bureau of Hamas, said by telephone from Gaza.

He accused Fayyad of cooperating with the United States and Israel in a crackdown on Hamas in the West Bank, jailing its members and shutting down institutions affiliated with the movement.

Fayyad’s name was not among the candidates considered in previous discussions between Fatah and Hamas, Bardawil said.

Mahmoud Zahar, another Hamas leader, said by telephone that Fatah had presented Fayyad’s appointment as an ultimatum, contrary to an agreement to reach a consensus on any candidate.

“This is a violation of the agreement,” Zahar said. “We’re speaking about principles, not particular names.” He said that he was “not accepting or rejecting” Fayyad but that the decision about the future prime minister had to be hammered out by the factions.

Saeb Erekat, an aide to Palestinian Authority President Mahmoud Abbas and a member of Fatah’s Central Committee, said that names had not yet been submitted for formal consideration and that Hamas was waging a campaign against Fayyad in the media. “We should not conduct these negotiations over the airwaves but leave them to the official consultations,” he said.

Although the factional accord faces significant obstacles, it appears to have reinforced a calm along Israel’s border with the Gaza Strip, where there have been virtually no rocket attacks from Gaza since the last flare-up of violence nearly two months ago.

Analysts said Hamas and other factions in Gaza do not want to be seen as upsetting efforts to carry out the accord, which has strong support among Palestinians. Neither do the groups want to antagonize Egypt, which brokered the pact and wants to prevent a renewed slide into cross-border violence, the analysts said.

“Without the cease-fire, the reconciliation between Hamas and Fatah might not be able to survive and succeed,” said Mkhaimar Abusada, a political scientist at al-Azhar University in Gaza. Palestinian factions that have been involved in firing rockets “don’t want to give Israel an excuse to derail the reconciliation and provoke Israel by launching of missiles,” he added.

The unity pact has also cemented an understanding among the factions about the advantages of maintaining quiet, said Khalid Amayreh, a Palestinian journalist in the West Bank who is considered close to Hamas. “Both Hamas and Fatah view the calm as a paramount Palestinian national interest” that averts devastating Israeli military strikes and deprives Israel of grounds to claim that Palestinian violence is preventing progress toward peace, Amayreh said.

Zahar, the Hamas leader in Gaza, said the mission of his organization, which rules Gaza and has enforced a cease-fire on smaller radical factions, was not solely armed confrontation with Israel.

“Resistance is an idea: to refuse injustice, to refuse occupation, to refuse aggression,” he said. “Resistance is not armed struggle alone.”