Venezuela's electoral authorities say an audit of the vote on President Hugo Chavez's rule found no proof of fraud.
The results mean Mr Chavez should remain in office until January 2007
"The results of the audit were very positive... allowing us to turn the page," said National Electoral Council director Jorge Rodriguez.
Mr Chavez won 59% of the vote in the 15 August poll, sparking claims of vote-rigging from the opposition, who refused to take part in the review.
It is the third time that international observers have endorsed the result.
The audit was carried out by the Venezuelan National Electoral Council and international observers from the Carter Center and the Organization of American States (OAS).
They checked the results produced by voting machines in 150 randomly chosen polling stations against paper records.
But the main opposition parties refused to send anyone to observe, saying the review would not properly investigate their allegations of massive fraud. They believe new electronic voting machines may have been rigged.
About 150 voting machines were checked against the paper records
But secretary-general of the OAS, Cesar Gaviria, said there was no proof of fraud.
"In our opinion, the type of check used in this audit of the electronic system doesn't leave us much doubt regarding the result," Mr Gaviria said at a news conference on Saturday.
"We cannot say categorically there was no fraud, we are saying we didn't find it."
The BBC's James Menendez in Caracas says the result of the audit leaves the opposition with few options.
He says that if they refuse to accept the result, that could damage their credibility, both at home and abroad.
But if they accept defeat, the lack of a common goal could cause the coalition of political parties, business leaders and trade unions to collapse.
Differences are already emerging, our correspondent notes.
The Venezuelan opposition is crying foul
Some opposition leaders are proposing a campaign of street demonstrations, while others are already talking of the need for dialogue with the newly empowered government.
The opposition has fought a tireless campaign to see Mr Chavez ousted. The president survived a short-lived coup in April 2002 and a two-month strike that badly damaged the economy later that year.
The referendum was called after the opposition collected signatures from 20% of the population - a recall mechanism inserted into the constitution by Mr Chavez in 1999.