Gaza's Hamas rulers issued rare criticism Thursday of Palestinian rocket attacks on Israel from the strip, saying now is the wrong time for such attacks.

The Islamic militant group has fired thousands of rockets at southern Israel in recent years. But Hamas said Thursday that it was not behind recent attacks and that it was investigating who was responsible.

It apparently fears that new rocket fire could disrupt the reconciliation talks currently underway in Cairo.

A Hamas spokesman says Palestinian factions trying to hammer out a power-sharing agreement are struggling to reconcile their differences toward peace talks with Israel.

Fawzi Barhoum says the disagreement is one of the key hurdles holding up the formation of a new unity government between the militant Hamas group and the more moderate Fatah faction.

Meanwhile, Egypt, which is mediating between rival Palestinian factions in the talks that began this week in Cairo, and Palestinian President Mahmoud Abbas' Fatah have repeatedly said that any new Palestinian government should accept previous peace agreements with Israel and Arabs' peace overtures to Israel.

That would include recognizing Israel's right to exist - which Hamas rejects.

"We were not part of these agreements, and therefore, no one should expect us to endorse them," Barhoum told The Associated Press in Cairo.

Egypt has set a Saturday deadline for the factions to produce an agreement and hopes to host a signing ceremony by the end of March.

Several negotiators at the talks said Egypt's powerful intelligence chief Omar Suleiman will meet the delegates Thursday to try to reconcile their differences. They spoke on condition of anonymity because they were not authorized to talk to the media.

They also said that Hamas and Fatah still disagree on other issues, such as setting a date for new presidential and legislative elections for all Palestinians.

"Time is not a sword hanging over our necks. What is important is what we achieve," Barhoum said.

The Palestinian divide was made worse after Hamas violent takeover of Gaza in 2007 that split Palestinian territory between the West Bank, controlled by the internationally backed Fatah, and the Gaza Strip, ruled by the widely shunned Hamas.

Overcoming the distrust between them is key to moving ahead with reconstruction in Gaza after Israel's recent offensive there. Previous unity accords have collapsed in mistrust and infighting, but this time both sides appear to have a strong incentive to reach an accord.

Hamas is under pressure to mend fences with Fatah to help end the devastating blockade of Gaza imposed by Egypt and Israel and obtain foreign funding to rebuild Gaza.

Fatah and Abbas, whose popularity took a beating due to his perceived lack of decisiveness during the Gaza war, need to find a way to blunt the challenges from Hamas.

The delegates in Cairo are working in five committees, deliberating specific issues - from forming a unity government, holding new elections, reforming the security services, carrying out confidence-building measures and finding a role for Hamas in the Palestine Liberation Organization. Other Palestinian factions are also present.