"Following discussions among the principals, today the Quartet dealing with the Middle East is announcing the appointment of Tony Blair as the Quartet representative," Montas told a noon press briefing at the UN headquarters.

Montas, reading a statement issued by the Quartet, said Blair, "who is stepping down from office this week, has long demonstrated his commitment on these issues."

"As Quartet representative, he will mobilize international assistance to the Palestinians, working closely with donors and existing coordination bodies," she said.

Blair will "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," the statement said.

The former British premier will "develop plans to promote Palestinian economic development, including private sector partnerships, building on previously agreed frameworks" and " liaise with other countries as appropriate in support of the agreed Quartet objectives," it said.

He will be supported in the new post by a small team of experts, based in Jerusalem, to be seconded by partner countries and institutions, according to the statement.

Envoys of the Quartet had a three-hour meeting Tuesday in Jerusalem to discuss issues concerning the recent developments in the region, including the naming of Blair as their special envoy.