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, which was formed during last year's revolt, will then be dissolved.The change marks the first peaceful transition of power in Libya's modern history.The 200-member assembly 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, the assembly's oldest member, will take place at 23:00 (21:00 GMT) on Wednesday, scheduled late because of Ramadan, the Muslim month of fasting.Security is likely to be the biggest challenge for Libya's new rulers, as numerous militia groups continue to grapple for influence.The assembly was elected on 7 July in the country's first free and fair polls in decades and is a mixture of independent candidates and political parties.Out of the 80 seats reserved for parties, the broadly secular National Forces Alliance, led by ex-interim Prime Minister Mahmoud Jibril - gained 39 seats, more than any other grouping.On Monday, members of the assembly informally agreed on the need to select a head of the assembly and two deputy chiefs within a week, independent member Salah Jawooda told AFP news agency.Former Libyan leader Col Muammar Gaddafi came to power in 1969 and ruled autocratically for more than four decades, until he was toppled and killed last year.Prior to this year's polls, the last national vote was held in 1965, when no political parties were allowed.