Zimbabwe's president has signed into law an amendment to the constitution that allows him to choose a successor if he decides to retire mid-term.
President Mugabe intends to run in elections next year
Robert Mugabe's choice would then be voted in by parliament which is dominated by his Zanu-PF party.
The constitutional amendment bill, which also allows presidential and parliamentary polls next March, had the backing of Zanu-PF and the opposition.
Mr Mugabe has said that he will seek another term in next year's elections.
Analysts say they expect Zanu-PF to dominate the joint elections in March 2008 and for Mr Mugabe to then put a hand-picked successor in place.
Spirit of consensus
The constitutional amendment was approved by parliament in September with the backing of the opposition Movement for Democratic Change (MDC) as a sign of goodwill.
Mr Mugabe, 83, has led Zimbabwe since independence from the UK in 1980.
The country is in the grip of a deep economic crisis which has seen inflation soar to more than 7,800%.
But more consensus has emerged recently between the MDC and the government following talks mediated by South Africa's President Thabo Mbeki.
The MDC said it supported the changes because the amended constitution would put an end to appointed MPs and make the commission in charge of re-drawing electoral boundaries more independent.