Blair, who steps down as Prime Minister on Wednesday, may be used to try and boost the prospects of a Palestinian state despite Hamas' takeover of the Gaza Strip.
It is believed that officials are trying to define a role Blair could undertake whereby he would be a peacemaker on four fronts; for the US, the EU, the UN, and Russia.
Top officials representing US Secretary of State Condoleezza Rice, UN Secretary-General Ban Ki-moon, EU foreign policy chief Javier Solana and Russian Foreign Minister Sergei Lavrov will be meeting in Jerusalem 26 June, and Blair's role is expected to be top of their agenda.
Sources said that an announcement was imminent, although Blair may not start work immediately. One European diplomat told Reuters: "There are consultations going on between members of the Quartet and the UK about appointing Tony Blair as Quartet envoy to the Palestinians. I cannot say whether there is a result, but I expect a result possibly on Tuesday when the Quartet envoys meet, perhaps even sooner."
Although Blair seems a popular choice as a peacekeeping envoy, there are some doubters who say that his close relationship with US President George Bush may hinder his effectiveness. In particular, some are weary of him being able to win Arab support after taking such a supportive role in the Iraq War with the US President.
