Talks between the Palestinian factions Fatah and Hamas on the composition of a shared government failed Tuesday to produce agreement on a prime minister, and the groups’ top leaders will meet next week in an effort to resolve the dispute, officials from both sides said.

The discussions in Cairo followed the signing of a reconciliation accord last month, which was meant to end a bitter four-year rift between the rival factions. The pact called for the formation of a joint government of unaffiliated technocrats to prepare for elections in a year, but progress in implementing it has been slow.

Hamas has rejected Fatah’s nominee, Salam Fayyad, the current prime minister of the Palestinian Authority in the West Bank, who has strong Western backing and the confidence of foreign donor states. Hamas officials have accused Fayyad of serving U.S. interests and cooperating with Israel in a crackdown on the militant Islamist group in the West Bank.

Palestinian Authority President Mahmoud Abbas, who heads Fatah, and Khaled Meshal, the Damascus-based leader of Hamas, will head the next round of talks in a bid to hammer out an agreement on the choice for the crucial premier’s post, officials from both factions said.

Salah Bardawil, a senior Hamas official in the Gaza Strip, said that his group had ruled out any further discussion of Fayyad’s candidacy, but Muhammad Shtayeh, a member of Fatah’s central committee, said that Abbas would try to persuade Meshal to accept his choice.

The dispute over the nominee for prime minister is the first serious snag in carrying out the reconciliation accord, whose details remain to be worked out. The two factions remain at odds over many issues.