Tony Blair was named the international envoy to the Middle East to spearhead efforts to create a Palestinian state, hours after stepping down as British prime minister.
"Following discussions among the principals, today, the quartet dealing with the Middle East is announcing the appointment of Tony Blair as the Quartet representative," UN spokeswoman Michele Montas announced on Wednesday.
She said that as "Quartet representative, Blair will mobilise international assistance to the Palestinians, working closely with donors and existing coordinating bodies."
Blair, 54, will also "help identify and secure appropriate international support in addressing the institutional governance needs of the Palestinian state, focusing as a matter of urgency on the rule of law," a Quartet statement said.
The so-called Middle East Quartet, comprising the European Union, Russia, the United Nations and the United States, has since 2003 tried to implement a "roadmap" for Israeli-Palestinian peace.But the three-stage blueprint that should have led to the creation of a Palestinian state living side by side in peace with Israel by 2005 has since languished.
The post of Quartet representative had been vacant since former World Bank chairman James Wolfensohn left in frustration in May 2006.
Several world leaders led by US President George W Bush welcomed Blair's appointment but the Palestinian Islamist movement Hamas denounced it.
"Tony will help Palestinians develop the political and economic institutions they will need for a democratic, sovereign state able to provide for its people and live in peace and security with Israel," Bush said.
Israel and Palestinian president Mahmud Abbas also expressed their approval.
Israeli Prime Minister Ehud Olmert "believes that Blair can have a favorable impact, in particular by helping the Palestinians develop solid governmental structures," his spokeswoman Miri Eisin said. Abbas, on a visit to Amman, agreed.
"President Abbas welcomes the nomination of Blair as envoy of the Quartet...(and) has given the assurance that he will work with (him) to arrive at a peaceful solution on the basis of two states," chief Palestinian negotiator Saeb Erakat told AFP.
But rival Hamas, whose forces routed Abbas' Fatah forces and seized control of the Gaza Strip 12 days ago, said the appointment "is not acceptable to Hamas nor to the Palestinians."
"He will not do anything to support the Palestinian interests but will do everything to support the Israeli occupation," Hamas spokesman Fawzi Barhum told AFP in Gaza.
Blair was tasked with developing plans to "promote Palestinian economic development, including private sector partnerships, building on previously agreed frameworks, especially concerning access and movement."
He was to be supported in his new job by a small team of experts based in Jerusalem and seconded by partner countries and institutions.
Speaking before parliament for the last time as prime minister, Blair said "the absolute priority is to try to give effect to what is now the consensus across the international community that the only way of bringing stability and peace in the Middle East is a two-state solution."
He said this means "a state of Israel which is secure and confident in its security, and a Palestinian state that is not merely viable in terms of its territory but in terms of its institutions and governance."
The Quartet statement said Blair would work "to help create viable and lasting government institutions representing all Palestinians, a robust economy, and a climate of law and order for the Palestinian people."
Blair's appointment was announced after Russia signaled it would not oppose the move.
Although he is well regarded in Israel, Blair has been reviled in the Arab world for Britain's role in the 2003 US-led invasion of Iraq and his support of Israel's war in Lebanon last summer.
Questions have therefore been raised as to whether this might not hurt his credibility as Middle East envoy, particularly among Arabs.
Canada -- the first country to suspend aid to a Hamas-led Palestinian government in March 2006 -- congratulated Blair on his new role, in a statement from Foreign Minister Peter MacKay.
"With his experience and commitment to this issue, we are confident that Blair will make an important contribution to building the conditions for a return to the peace process," he said.