CAIRO (AFP) — Egypt was on Tuesday holding talks with Hamas on Cairo's Gaza truce proposal, with an official calling for the Islamists to sign up "now" in the hope of announcing a ceasefire before the end of the week.

A Hamas delegation was to hold a fresh round of talks with Egyptian intelligence chief Omar Suleiman, as Israel's offensive ploughed on for an 18th day and diplomatic efforts to end the bloodshed plodded forward.

"We're working seriously with Hamas, we need to end the vagueness and they need to say yes, now, to our plan," a senior Egyptian diplomat told AFP, requesting anonymity.

"Egypt hopes that the Israeli war machine can be stopped by the end of the week and the massacres can be ended," with more than 900 Palestinians dead and 4,000 wounded.

The diplomat said that Israel "appears now to agree" with the truce plan launched by Egyptian President Hosni Mubarak a week ago, but Hamas is having difficulty signing up to it.

The plan calls for a ceasefire for a pre-determined time, securing tunnels which Israel says are used to smuggle weapons from Egypt into Gaza, opening the embattled enclave's borders and restarting Palestinian reconciliation talks.

"Hamas delegates coming from Damascus demonstrate the luxury of patience while those from Gaza are in more of a hurry to end it," the diplomat said. "Syria could clearly play a more positive role."

The Hamas negotiating team is made up of five officials, three from the exiled political leadership in Damascus and two from the Gaza Strip.

"The problem is that until now there have been no real negotiations, no engagement or clear answers from them," the diplomat said.

The Syria-based Hamas delegates have been shuttling between Cairo and Damascus for the last few days, reporting their talks to the exiled leadership.

Two of the divisive issues are the possible presence of a multinational observer force on the Palestinian side of Egypt's 14-kilometre (nine-mile) border with Egypt and the duration of an eventual truce.

"Hamas says it doesn't want this force while Israel does, and the Jewish state wants an indefinite truce and the Islamists want it to be for a fixed period of time, around six months," the diplomat said.

He said that Israel's main negotiator, senior defence official Amos Gilad, is "ready and waiting" to return to Cairo, after an initial round of talks with Egypt's Suleiman.

The two men brokered the last six-month Israel-Hamas truce which ended in December, heralding the latest violence. Suleiman has negotiated previous truces with different Palestinian factions in 2001, 2003 and 2005.

"It appears, through various signals, that Israel accepts our plan but is not ready to announce it publicly," the Egyptian diplomat said.

"The concept of the new truce has not changed, but on top of an agreement between the two parties not to use violence, it must be applied with undertakings, guarantees and multinational controls," he said.

Such guarantees and controls must include securing borders -- Israel's demand of an end to arms trafficking through tunnels into Gaza -- and "opening border crossings and lifting the siege," as demanded by the Palestinians.

Another key element is the Palestinian reconciliation process aimed at bringing Hamas and the rival Fatah of president Mahmud Abbas -- who reigns in the occupied West Bank -- back together again.

Hamas's Gaza-based political leader Ismail Haniya said on Monday that any truce plan must stipulate "a withdrawal of Zionist forces," as well as an "end to the aggression," and ending the blockade by opening border crossing points.

"The Egyptian plan will work out," the diplomat said.