Venezuela’s electoral body has said the audit of votes cast in the presidential election will start on 6 May
But it will not carry out the full recount demanded by opposition candidate Henrique Capriles, who lost narrowly to President Nicolas Maduro on 14 April.
Mr Capriles called the audit a fake, accusing the electoral council (CNE) of following the government’s orders.
CNE president Tibisay Lucena said Mr Capriles’ demands were “unfeasible”.
The opposition leader reacted angrily to Ms Lucena’s announcement on national television.
‘Fools’
“Again they think Venezuelans are fools! Without [comparing] the vote tallies, the audit is a fake!” he wrote on Twitter.
Mr Capriles also wrote that it was “impossible that Ms Lucena would say anything against the order she was given” by the governing party.
The CNE said the audit would start on 6 May and should be completed by 4 June.
Hours after the poll close on 14 April, the authorities announced the victory of Nicolas Maduro, the handpicked successor of the late President Hugo Chavez.
But the margin of less than two percentage points was promptly contested by Mr Capriles, who denounced dozens of alleged cases of voters being coerced to cast ballots for the government’s candidate.
When the CNE first announced it would audit the votes, the opposition leader at first agreed with it.
But on Thursday, he pulled out of the process and called it “a joke.”
On Sunday, Mr Capriles repeated that he would use “all the available instances” to fight Mr Maduro’s victory.
He had already vowed to challenge it in the Supreme Court.
Mr Capriles says he will ask the Supreme Court to annul the election and allow Venezuelans to go back to the polls.
Despite the controversy, Mr Maduro was sworn in as president on 19 April, succeeding his mentor Hugo Chavez, who died in March of cancer.
Nine people died in post-election protests. Both the government and the opposition are planning more protests on 1 May.
State media reported that pro-opposition mobs were torching health clinics but opposition media said that many reports of violence were fabricated.