Palestinian armed factions in the Gaza Strip are observing a 24-hour halt to rocket fire against Israel at the request of Egyptian mediators, a senior official of the ruling Islamist Hamas group said on Monday.

Ayman Taha said the brief ceasefire went into effect on Sunday evening. He said Hamas mighty consider a longer truce if Israel were to reciprocate by ceasing all military attacks in Gaza and lifting an embargo on the impoverished territory.

A six-month Egyptian-brokered truce between Israel and Hamas expired on Friday with exchanges of fire across the border, raising fears of a wider conflict.

"Hamas and other factions agreed in order to give a chance to the Egyptian mediation and to show that the problem was always on the Israeli side," Taha told Reuters.

"If a new (truce) offer were made, which met our demands, then we would be willing to study it."

The surge of Palestinian rocket fire and Israeli air strikes over the weekend prompted calls in Israel to launch a wider offensive in Gaza.

Taha said any such escalation would be met by Palestinian retaliation including suicide bombings inside the Jewish state.

Israeli government officials were not immediately available to respond to Taha's statements.

An Israeli military spokesman said that, as of Sunday evening, Palestinians in Gaza had fired at least one rocket and four mortar bombs across the border.