The power struggle within the Palestinian Authority leadership heated up yesterday, with associates of Chairman Yasser Arafat demanding the powers of Security Minister Mohammed Dahlan, who is Prime Minister Mahmoud Abbas's protege, be limited.

Meanwhile, in Gaza, an Egyptian delegation met with Hamas spiritual leader Sheikh Ahmed Yassin and asked him to extend the three-month cease-fire to six months. Yassin's response, however, was noncommittal.

Efforts to mediate between Arafat and Abbas (Abu Mazen), after the latter quit Fatah's Central Committee earlier this week, focused last night on Arafat's bid to reduce Dahlan's powers.

Central committee members, acting at Arafat's behest, charged that Dahlan - with Abbas' compliance - has assumed powers not granted to him by the constitutional laws under which the government was formed more than two months ago. Arafat's associates are demanding that various security powers currently held by Dahlan revert to the Palestinian National Security Council, which Arafat established after the Abbas government was formed and currently heads.

In recent weeks, Dahlan has assumed acting control of the Palestinian Interior Ministry, which is officially in Abbas' hands. And with Abbas' approval, Dahlan has been implementing structural reforms, making a series of appointments and rebuilding the police and Preventive Security forces, the two security forces that are under the ministry's authority.

Dahlan has largely taken over the formal running of the ministry, with relatively little intervention by Abbas. Haaretz has obtained a copy of a document sent by Dahlan that carries the ministry's new logo and is signed by Dahlan as "Minister for Security in charge of the Interior Ministry."

But despite Dahlan's activities, the National Security Council, which is staffed by security officials aligned with Arafat, was the body that formally gave instructions to the heads of the security forces - and to Dahlan - to prepare for the Israeli withdrawal from Gaza and Bethlehem and to assume security responsibility for those areas.

In Gaza, an Egyptian intelligence services delegation, headed by deputy chief Mustafa Elbuheiri and Mohammed Ibrahim, met with Sheikh Yassin to press him to extend the three-month cease-fire declared last week to six months, but did not obtain a definite response.

Egypt has played a key role over the last year in trying to win pan-Palestinian approval for a cease-fire, and it was instrumental in persuading Hamas and Islamic Jihad to agree to a three-month cease-fire last week.

At the end of the meeting, Yassin emphasized that Hamas was committed to the cease-fire. "We explained to the Egyptian representatives that we are commited to the cease-fire, despite the Israeli violations of the agreement. But our patience also has a limit, and the enemy must show responsibility and display commitment to the initiative so that the situation doesn't go back to what it was before the cease-fire ... There's a need for prisoners who have been in jail a long time to be released, as well as women, children and the ailing," he said.

He did not say what his response was to the Egyptian pressure for a longer cease-fire, only saying that "they talked about it."

Hamas sources said that Egypt wants to conduct another round of meetings with Palestinian factions in Cairo in order to strengthen the cease-fire. But Hamas wants to downplay Egyptian involvement at this stage, apparently to avoid Egyptian efforts to bring Hamas into an overall national Palestinian leadership that would establish ground rules for the elections planned during the second phase of the road map peace process. Hamas has not accepted the road map, because it implies acceptance of Israel. Yassin said yesterday that "the Egyptians wanted to continue the Palestinian dialogue in Cairo, but there is no need for that."

Abbas has met with Yassin at least once since becoming prime minister.

In another development, Khaled Mashal, the head of Hamas' political bureau, yesterday warned Abbas and Dahlan against trying to collect Hamas weapons, a key demand of Israel's that is backed by the United States. In an interview with the London-based Al Hayyat, Mashal said: "Any attempt to implement the American and Israeli security plan to grant security to Israel or to cooperate with the plan to eliminate the military resistance and collect weapons will open tunnels that have no end. I won't add anything to that."