A group of international observers who monitored Mexico's disputed presidential election called for the full recount demanded by the leftist candidate Thursday, saying it had witnessed fraud on election day and that recounting all 41 million ballots would resolve doubts about the result.

Ted Lewis, the director of Global Exchange, called for the recount even though he said he can't say whether the fraud his observers witnessed was significant enough to erase the lead of conservative Felipe Calderon and swing the election to leftist Andres Manuel Lopez Obrador.

Global Exchange, a leftist group based in San Francisco, observed voting at 60 of the country's 130,000 polling places and found evidence of fraud or irregularities at each of them, Lewis said, including polling places with more ballots cast than registered voters, intimidation, vote-buying, the unauthorized intervention of political leaders and a lack of knowledge among volunteer poll workers.

"Yes, there was fraud, from what we could see, in small things," Lewis said. "We can't say that this would affect the final result. ... We aren't applying this to the whole country, nor are we generalizing."

Lopez Obrador has insisted that a full recount would expose rampant fraud and swing the election his way.

Instead, the Federal Electoral Tribunal ordered a recount of 9 percent of the ballots, and while the judges still haven't made the results public, both political parties involved said changed vote totals fell far short of what would be needed to reverse the initial 240,000 vote lead of the ruling party's Calderon.

Calderon has said the election was clean and called on Lopez Obrador to accept the court's final decision. The judges have until Sept. 6 to announce a president-elect or annul the election.

The initial count was prepared by the Federal Electoral Institute, or IFE, which has been held up internationally as a model of a fair and objective organization, and has advised emerging democracies including Iraq and Haiti. But some fear its reputation has been damaged by the complaints of fraud.

"One way for the Federal Electoral Institute to recover its reputation as a fair and open institution is to attend to the petition from a growing number of Mexicans to conduct a recount of the vote," Lewis said.

It is the Federal Electoral Tribunal, however, IFE, that will certify the results, and it has already rejected a wider recount.

A spokeswoman for the IFE told The Associated Press that the institution would not comment until the court rules.

Lewis said Global Exchange also recommended that Mexico reform its election laws to allow a second round of voting in extremely tight races to "guarantee the legitimacy of the winner" as well as reduce the length and cost of campaigns.

Also Thursday, President Vicente Fox's spokesman, Ruben Aguilar, said Fox planned to deliver his annual state-of-the-nation address to Congress as usual on Sept. 1, despite threats by Lopez Obrador supporters, who said they would ensure that the event "would be no picnic" for the president.