TUNIS, Tunisia - Tunisia's new assembly chose a veteran rights activist Monday as the country's first democratically elected president.

Moncef Marzouki of the Congress for the Republic Party became the interim president with 153 out of 217 votes in the assembly; three members voted against, two abstained, and 44 cast blank ballots as a protest vote.

"It is the greatest honor that anyone could dream of being elected by two-thirds of the vote," Marzouki said after the election, which was followed by a rendition of the national anthem. "I will exert all my efforts to be worthy of this trust."

Marzouki for years struggled against Tunisia's dictator President Zine el-Abidine Ben Ali and was imprisoned in 1994 for trying to run against him as president.

Marzouki, who succeeds interim President Fouad Mebazzaa, will be Tunisia's fourth president since its independence from France in 1956.

His election follows the weekend approval of temporary bylaws to guide Tunisia until the assembly finishes a constitution. It also comes six weeks after landmark elections and nearly a year after Tunisians overthrew Ben Ali - an uprising that sparked similar movements in other Arab states.

The new bylaws give most of the power to the prime minister, rather than the president - a change that worries the opposition. The bylaws also stipulate that the president must be Muslim with Tunisian parents, over 35, and not a dual citizen of another country. Tunisia is 98 percent Muslim, but it also has some Jewish and Christian citizens.

Marzouki is expected to appoint a prime minister from the moderate Islamist Ennahda Party, whose ruling coalition also includes the left-of-center Ettakatol Party. The prime minister then has 21 days to form a government, which will be in effect temporarily until the country holds post-constitutional elections.

Although the bylaws passed with the coalition's comfortable majority, many were harshly contested by the opposition, which consists mainly of liberal and left-wing parties. Nejib Chebbi of the Progressive Democratic Party warned of "a new dictatorship."

Ennahda, which was severely repressed by the old regime, has said its goal is to ensure that there can never be another dictatorship in Tunisia. It also has gone out of its way to reassure secular Tunisians that it has no plans to impose religious values on one of the more Westernized countries in the Middle East.