Barack Obama has picked Senator Joe Biden of Delaware as his US vice presidential running mate, a Democratic party official said today.

Democratic rivals Barack Obama and Hillary Rodham Clinton turned up the rhetoric in their increasingly heated presidential primary battle.

US presidential candidate John Kerry was today expected to announce his choice of running mate to take on George Bush and the Republicans for control of The White House.

US president George Bush is spelling out details tonight of the handover of power to an Iraqi government, in an attempt to calm fears about rising casualties and spreading violence.