Palestinian Authority President Mahmoud Abbas on Saturday postponed parliamentary elections indefinitely, giving his embattled Fatah party time to halt political infighting and shore up support against a growing challenge from the Islamic Resistance Movement, or Hamas.

Hamas accused Abbas of stonewalling but said it would continue to honor an informal cease-fire with Israel. No new date was announced for the election, which was originally scheduled for July 17.

Tapping into voter dissatisfaction with entrenched Fatah corruption, Hamas has won several key races in recent local elections and appears poised to make strong gains in the legislative vote as well. This will be the first time Hamas has participated in legislative elections.

Abbas said Saturday that more time was needed to resolve differences over a new election law. He wants all candidates chosen from national lists, while some Fatah members in parliament prefer voting by district.

"Time is short," Abbas said in an interview with Palestinian television. "Postponement was necessary to allow us to finalize the legal measures and consultations between factions."

He said a new election date would be set after discussions with the legislature and rival political parties.

Hamas accused Abbas of ordering the delay to try to improve Fatah's chances.

"This decision was taken unilaterally . . . and it came as a response to the conditions and the atmosphere of the Fatah movement and not because of any national consideration," said Sami Abu Zuhri, a Hamas spokesman in the Gaza Strip.

While accusing Abbas of violating the cease-fire agreement, Abu Zuhri indicated that Hamas would continue to honor the truce. But he said Abbas's decision might harm relations with Hamas.

Abbas reached the cease-fire agreement with Israeli Prime Minister Ariel Sharon on Feb. 8 in an effort to end more than four years of fighting between the Jewish state and the Palestinians.

Hamas and other groups agreed in March to honor the truce in return for pledges from Abbas to give them a formal role in Palestinian decision-making. Violence has dropped sharply since then. Recently, however, Hamas threatened to pull out of the truce if the election was delayed.

Palestinian leader Mahmoud Abbas did not set a new date for the vote.