UNITED NATIONS, (Reuters) – The Middle East negotiating Quartet has appointed former British prime minister Tony Blair as its representative, the United Nations announced on Wednesday.

Blair, who stepped down as premier on Wednesday, “has long demonstrated his commitment on these issues,” U.N. spokeswoman Michele Montas told a regular news briefing. She said Blair would “mobilize international assistance for the Palestinians, working closely with donors and existing coordination bodies.” He would also help secure international support for the governance needs of the Palestinian Authority, focusing on the rule of law, and work out plans to promote Palestinian economic development, she said.

The Quartet consists of the United Nations, the United States, Russia and the European Union.

Blair himself has acknowledged the difficulties of a high-stakes peacemaking role meant to steer the Palestinians towards statehood following Hamas’s violent takeover of the Gaza Strip.

Some European diplomats have raised questions about Blair’s ability to garner broad Palestinian and Arab public support because of his leading role in the Iraq war and his close relationship with U.S. President George W. Bush.

The White House was quick to welcome the appointment. Spokesman Gordon Johndroe said: “The president welcomes this announcement, appreciates his willingness to serve and to continue his (Blair’s) work for peace in the Middle East.”

An Israeli official said: “We welcome the Quartet’s decision. We think that Prime Minister Blair is very involved, understanding and will be a very positive influence on the Middle East peace process.”

Blair earlier spoke by telephone to Russian President Vladimir Putin, whose government had been holding up his appointment. “The Quartet has concluded the elaboration of a mandate for the new representative,” Russian Foreign Minister Sergei Lavrov said in the West Bank city of Ramallah when asked if Moscow would support Blair.