A fragile truce between Israel and the Palestinian Islamist movement Hamas came into force in the Gaza Strip on Thursday amid scepticism over how long the Egyptian-brokered deal would hold.

It is the first formal ceasefire since Hamas's bloody takeover of the impoverished territory just over a year ago which triggered a crippling Israeli blockade against what it brands a "hostile entity."

"The truce came into effect at 6am (0300 GMT)," Hamas spokesperson Sami Abu Zuhri. "Hamas is determined to respect the truce and guarantee its success."

There was no immediate comment from the Israeli army.

But underscoring the fragility of the deal, the two sides traded a barrage of fire on Wednesday and just minutes before the guns fell silent on Thursday a Palestinian was killed by Israeli fire targeting rocket launchers in Gaza City.

As well a halt to militant rocket fire and Israeli strikes on Gaza , the deal calls for Israel to progressively ease its blockade of the territory where most of the 1.5 million population in the overcrowded strip of land depend on aid.

Israeli Prime Minister Ehud Olmert, whose government boycotts Hamas as a terrorist outfit, warned on Wednesday that the ceasefire would be "fragile" and could be "short-lived".

"If terror continues, Israel will have to work to remove the threat," he said, describing Hamas as "despicable, bloodthirsty terrorists who have not changed."

Indirect Egyptian negotiations

Egypt announced the deal on Tuesday after months of brokering indirect negotiations between Hamas and Israel, which had been mulling a wider military offensive in Gaza in a bid to halt rocket fire.

It comes seven months after Israel-Palestinian peace talks were revived at a US conference in November, although they have made little visible progress in part because of the Gaza violence and Jewish settlement activity.

At least 516 people have been killed in Israeli-Palestinian fighting since November, most of them Gaza militants. Since Hamas seized Gaza in June last year, three people in Israel have been killed by rocket fire.

World leaders welcomed the truce news but Israelis and Palestinians were wary.

"They make agreements and ceasefires here and there all the time. We will wait until we see real results," said Hatem, a 30-year-old baker in Gaza City.

Just five kilometres away, in the Israeli town of Sderot, scarred by hundreds of rocket attacks, government employee Georges Adjedj insisted that military action alone was needed to pacify Gaza.

"Only when the IDF (army) is inside Gaza does calm prevail," he said.

Easing the blockade

Senior Hamas official Khalil al-Hayya said border crossings used to import goods into Gaza would be partially opened several hours after calm settles in, while talks to open the Rafah border with Egypt could follow a week later.

Olmert's spokesperson Mark Regev said Israel would ease the Gaza blockade only "if the fighting indeed ceases Thursday as planned."

Israel has linked the opening of Rafah, Gaza's only link to the outside world that bypasses Israel, to the release of Gilad Shalit, a soldier captured in a Palestinian commando raid two years ago.

"If Gilad Shat is not released, the Rafah crossing will not reopen," top defence ministry official Amos Gilad told the Ynet news website.

On the eve of the truce, Israel carried out two air raids on northern Gaza, wounding two gunmen, while militants fired 40 rockets and mortar rounds at southern Israel, injuring one woman.

The White House cautiously welcomed the deal, saying the United States hoped it meant Hamas, which won Palestinian elections in 2006, would "give up terrorism."

UN chief Ban Ki-moon said he hoped it "will both provide security and an easing of the humanitarian crisis in impoverished Gaza, and end rocket and mortar attacks against Israeli targets."

Syria, home to Hamas supremo Khaled Meshaal, said it supported the deal while the 22-member Arab League said it would be "an important step towards inter-Palestinian reconciliation."

The truce comes just a year after Hamas seized control of Gaza after routing forces loyal to President Mahmud Abbas on 15 June 2007 in the most vicious Palestinian infighting ever seen.

Abbas, whose writ has since extended only to the occupied West Bank, urged "all movements within the Gaza Strip to adhere to the truce."

AFP