QUITO, Ecuador (AP) -- Quito Mayor Jamil Mahuad has won Ecuador's presidential runoff, election officials announced, confirming preliminary results that showed the Harvard graduate defeating a banana tycoon who alleged election fraud.

Mahuad, who has a master's degree in public administration from Harvard, received 51 percent of the vote in the July 12 election, compared to 49 percent for populist Alvaro Noboa, the Supreme Electoral Tribunal said Sunday.

The announcement ended seven days of post-vote tension during which both candidates had claimed victory and Mahuad began meeting officials to form his new government.

Noboa told reporters Sunday he wouldn't recognize Mahuad's win and repeated his call for officials to recount the votes in his home province of Guayas, on Ecuador's Pacific coast.

In the days before the Tribunal's announcement, Noboa paid for radio and television ads calling on his supporters to hold peaceful vigils to protest what he said was fraud organized by the Mahuad camp.

OAS observers say the vote was fair

Observers from the Organization of American States have rejected the fraud charges, and pronounced the vote fair.

Mahuad, 48, and Noboa, 47, were the top vote-getters in the first round of voting on May 31.

Mahuad earned a reputation as an honest, effective politician during his six-year stint as Quito mayor. He had the support of Ecuador's political and business elite, who saw him as the best hope to end the chronic political instability of this Andean nation of 12 million people .

Noboa called himself the candidate of the poor despite his wealth, and promised to create a million jobs if elected.

When Mahuad takes office Aug. 10, he will replace an 18-month interim government led by Fabian Alarcon. Congress appointed Alarcon in February 1997 after removing eccentric President Abdala Bucaram from power for "mental incapacity."

Congress accused Bucaram of corruption and embarrassing public behavior during his six months in power.

Bucaram, a flamboyant populist who called himself "El Loco," or "The Crazy One," was known for his raucous public performances of "Jailhouse Rock" in Spanish and a CD called "A Crazy Man in Love."