Mahmoud Abbas, the Palestinian President, swore-in an emergency government in the West Bank yesterday, a move denounced as “illegal” by the dismissed Hamas Prime Minister, Ismail Haniya, whose Islamic movement has taken control of the Gaza Strip.

As the two rival Palestinian governments traded barbs, Israeli forces moved into the northern Gaza Strip. The Israeli company that provides fuel to Gaza shut off deliveries to all depots in Gaza except those feeding power stations.

Two Katyusha rockets were fired into the northern Israeli town of Kiryat Shmona from Lebanon, causing damage to vehicles and buildings but no injuries. The Lebanese Army said that it stopped the firing of a third rocket. Israel blamed Palestinian groups in refugee camps across the border.

Israel and the international community have rallied around Mr Abbas’s secular Fatah leadership — which has lost control of the Gaza Strip — and moved to stifle the new fiefdom established by Hamas, who were described yesterday by Saeb Erekat, the chief Palestinian negotiator, as “gangsters” who had carried out a coup d’état.

But Hamas likewise denounced the new emergency government headed by the former World Bank technocrat, Salam Fayyad, for executing a “coup” against the Hamas-led Government, which came to power 18 months ago in democratic elections.

With Gaza’s 1.4 million people trapped in the 140- square-mile coastal strip and facing imminent shortages, Mr Fayyad, the new prime minister in the West Bank, said that his emergency administration’s first task was to address the security situation.

Mr Abbas, in no mood to negotiate with Hamas, issued a decree outlawing the movement’s militia branches “due to their military coup against the Palestinian legitimacy and its institutions”.

The international community rushed to shore up Mr Abbas’s new government of moderates. Washington, which had refused funding for the Palestinians while Hamas was in power, said that it would lift a ban on direct financial aid to the new emergency government, clearing the way for the European Union and Israel to follow suit.

“There won’t be any obstacles economically and politically in terms of re-engaging with this government . . . They will have full support,” Jacob Walles, the US consul-general, said.

At the same time Israel is prepared to release frozen tax revenue worth about $600 million (£304 million) due to the Abbas government.

Ehud Olmert, the Israeli Prime Minister, is due in Washington today. Some sources suggest that President Bush will ask him to make other concessions such as dismantling roadblocks in the West Bank.

Hamas wing

— Political wing Formed in 1987, won the 2006 elections and formed a government first on its own then with Fatah

— Izz ad-din al-Qassam Brigades The armed wing formed in 1992. Responsible for military operations

— The Executive Force Created as a parallel police force with the aim of countering the influence of Fatah over the Palestinian Authority’s security forces

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