Manuel de la Pena y Pena -- president of the supreme court -- became acting president.

VOA: special.2009.02.26

Putin became acting president of Russia, the world has barely begun getting to know him.

CENTERFORSECURITYPOLICY: Restoration Watch: Putin's 'Remilitarization' Campaign

Mr Zhang became acting president of the AFC after his predecessor, Mohammed Bin Hamman, was given a lifetime ban by Fifa for corruption and bribery.

BBC: Asia

Goodluck Jonathan, Mr Yar'Adua's southern deputy, who became acting president in February as the country grew impatient, has already been sworn in and will soon appoint a vice-president, who may then be groomed as next year's candidate.

ECONOMIST: The death of Nigeria's president