Bolivia’s President, Evo Morales, has said he would call a new election after international monitors questioned the validity of his victory last month.
The Organization of American States (OAS), which monitored the elections, called for the result to be annulled.
Mr. Morales’s announcement comes after weeks of anti-government protests over reported irregularities and fraud.
Opposition leader Carlos Mesa said Mr. Morales and his vice-president should not run in the new poll.
Nor should they preside over the electoral process, he said.
If you have an iota of patriotism, you should step aside,” Mr. Mesa said at a news conference.
The president, who was first elected in 2006, has denied any wrongdoing and ignored calls to resign.
“The candidacies must be secondary; what comes first is to pacify Bolivia,” he told a local radio station.
In his announcement on Sunday, the president also said the country’s electoral body would be overhauled before the poll, with parliament choosing its members.
Mr. Morales, who is Bolivia’s first indigenous president, told reporters that he had made the decision “to reduce all tension.”