Former British Prime Minister Tony Blair's plans for general election campaigning could be disrupted as he is stranded in Jerusalem, his spokesman said Sunday.
Blair was due back at the weekend but much of Europe's airspace has been forced shut by the Icelandic volcano ash cloud.
Blair, who led the Labour Party to three consecutive general election victories, has already made one speech in support of his successor Gordon Brown ahead of the May 6 vote.
He now represents the European Union, Russia, the United Nations and the United States in the peace process between Israel and the Palestinians.
But his return to the domestic political scene has been delayed by the ash cloud.
"Tony Blair is in the Middle East in his role as Quartet representative at the moment," his spokesman said.
"He is planning to be back this week to rejoin the campaign trail but that is obviously subject to him being able to travel."
Blair, premier from 1997 to 2007, gave a speech last month to Labour Party members in his old Sedgefield constituency, praising Gordon Brown's "experience, judgment and boldness".
Centre-left Labour are trailing behind the main opposition Conservatives in opinion polls, with at least one poll putting them behind the Liberal Democrats as well.