The interim government in Libya is handing over power to a new General National Congress which was formed after last month's elections.
The interim government was made up of the opposition forces that toppled Colonel Muammar Gaddafi a year ago, and will be dissolved once power has been transferred.
NTC chief Mustafa Abdul Jalil will pass the reins to the oldest member of the legislative body at a late-night ceremony in the capital, Tripoli. The NTC will then be dissolved.
The BBC reports the change is the first peaceful transition of power in Libya's modern history.
The assembly, which has 200 members, will later appoint a government, which will rule until new elections following the drafting of a new constitution.
The transfer of power to Mohammed Ali Salim will take place at 11pm on Wednesday, scheduled late because of Ramadan, the Muslim month of fasting.
The assembly was elected on 7 July and is a mixture of independent candidates and political parties.
Colonel Gaddafi came to power in 1969 and ruled for more than four decades, until he was killed last year.
Prior to this year's polls, the last national vote was held in 1965, when no political parties were allowed.