LA PAZ — Bolivian President Evo Morales declared victory on Thursday in elections whose disputed results have triggered riots, a general strike and opposition charges that the leftist leader is trying to steal a fourth term in office.

Hours later, the Supreme Electoral Tribunal (TSE) on its website declared Morales the winner with 99.8 per cent of the ballots counted from Sunday's vote.

Morales had 47.1 per cent, the tribunal said, against 36.5 per cent for his closest rival, the centrist Carlos Mesa.

Mesa needed to be within 10 points of Morales to force a runoff.

The TSE has been heavily criticized for its conduct of the count process, including by its own vice-president, who resigned.

"We won in the first round," Morales confidently told an earlier news conference, calling it "good news."

But he said that if he did not obtain the 10-point margin he would respect that result.

"If we have to go to a second round, we will go," he said.

The new mandate means Morales, already Latin America's longest-serving president, will remain in power until 2025.

He stood for a fourth successive term despite Bolivia's constitution limiting presidents to two consecutive mandates.

Speaking at a rally in La Paz alongside center and right wing parties, as well as business leaders, Mesa called for a second round and urged his supporters to continue their industrial action in the streets of this resource-rich but poor South American country.

On Wednesday he had said he would not recognise results tallied by the tribunal, which he accused of manipulating the count to help Morales win.

Observers from the Organisation of American States have expressed concern over the vote count, which first showed Morales and Mesa in a tight race and headed for a runoff, then shifting dramatically Monday to give the president a wider lead.

The European Union said on Thursday it shared the OAS assessment "that the best option would be to hold a second round to restore trust and ensure the full respect of the democratic choice of the Bolivian people."

"We call on all parties to refrain from violence and from making declarations that are divisive," it said. — AFP