Israel and Hamas fought a devastating three-week war in the Gaza Strip two years ago and there have been frequent exchanges of fire across the tense border since, with incidents recently spiking.

Palestinians fired 26 rockets and mortars into Israel this week. An Israeli airstrike wiped out a five-man rocket squad and a Palestinian shepherd was shot dead near the border.

In front of a crowd of supporters in southern Gaza after Friday prayers, senior leader Mahmoud Al-Zahar said Hamas would be committed to a cease-fire if Israel abided by it.

Al-Zahar said Hamas and other factions were committed to an agreement they had reached last year to stop rocket firing into Israel, although smaller groups continued to launch attacks.

"We are committed to self-restraint as long as there is no oppression and no aggression," said Al-Zahar.

A spokesman for Israel's Foreign Ministry said Al-Zahar's declared intentions will be tested by the reality on the ground. "Hamas has escalated the situation, it can now be de-escalated by simply stopping the rocket fire," said Yigal Palmor.

The United Nations said Thursday both sides had indicated they wanted to reduce tension around the eastern Mediterranean coastal enclave.

Hamas also mocked a Fatah claim it could retake Gaza. The organization said any attempt to recover the strip which it has controlled since ousting Fatah from the densely populated territory in 2007 was doomed to fail.

"Fatah has a strategy to deal with the division if the (reconciliation) dialogue fails," Fatah Central Committee member Azzam Al-Ahmad told Asharq Al-Awsat newspaper in an interview. "We are capable of recovering Gaza. The people there will support us and there are measures which are more effective than weapons," he said, without elaborating.

The Hamas Interior Ministry dismissed Ahmad's comments and warned that "Fatah and its leadership will be held responsible for triggering any unrest" in Gaza.

The exchanges came after Hamas and Fatah held two rounds of fruitless reconciliation talks in Damascus in September and November, and with little hope of progress in coming months.