Tony Blair has landed a major diplomatic job as the international Middle East peace envoy, responsible for preparing the Palestinians for negotiations with Israel. His role, to be shortly announced, will be largely to work with the Palestinians over security, economy and governance.

Working from an office in Jerusalem, and possibly another in the West Bank, Mr Blair will become the special representative for the Middle East quartet of UN, EU, US and Russia. The announcement comes on the eve of his departure from Downing Street on Wednesday and is privately welcomed by Gordon Brown.

The arrangement, which has been under preparation for weeks, is due to be agreed at a meeting of the quartet on Tuesday. Friends of Mr Blair suggest he would make it a central purpose of his mission to work to restore Palestinian unity after the armed takeover of the Gaza Strip by the Islamist movement Hamas.

At times he has had to bend with an American willingness to bolster Mahmoud Abbas, the Fatah leader, while ignoring the plight of 1.4 million Palestinians in Gaza.
The idea of Mr Blair doing this job is understood to have originated with the prime minister himself in conversation with George Bush, who then suggested it to the UN. The UN secretary general, Ban Ki-moon, is said to be a keen supporter and Washington was reported on Monday night to have mounted “an enormous push” to ensure Mr Blair got the post. Diplomats said there was some disquiet over the way US talks with Mr Blair were well advanced before any details were shared with the other quartet partners.

Mr Blair has constantly pressed Mr Bush to take a more active role in securing a two-state solution for Israel and Palestine. Though his standing in the so-called Arab street may be low because of his role in the invasion of Iraq, he is held in high standing among Arab political elites, and he has frequently spoken of his passion to play a part in helping to secure peace in the Middle East.

It was being stressed that Mr Blair's role — in the short term at least — would not be to act as a mediator between the Palestinians and the Israelis, or to become a negotiator for the road map to peace. He might, however, be responsible for trying to persuade the Palestinians to accept the conditions for ending the international boycott of Hamas. The now defunct Hamas government has not received any international aid since its election in March 2006, although aid has been sent directly to the poorest Palestinians through a temporary international mechanism.

The quartet says aid can only be conditional on the Palestinians accepting the right of Israel to exist and giving a commitment to exclusively peaceful means and to abide by all previous agreements.

Critics have claimed the preconditions have impoverished the Palestinians, boosted unemployment and led to the radicalisation of Hamas, culminating in Hamas controlling Gaza, and Fatah the West Bank.