Former presidential candidate Henrique Capriles is among those who say their signatures have been ruled out for "failing to meet the requirements". The Speaker of the National Assembly, Henry Ramos Allup, described the move as "shameful" and "a provocation". The decision was announced on Friday by the National Electoral Council (CNE). The electoral body's president, Tibisay Lucena, said more than 600,000 signatures had been invalidated. The other voters who signed the petition - more than 1.3 million people - will need to turn up at regional electoral offices to confirm their identity later this month. Voters will have five days from 20 June to have their signatures checked.
'Dead voters and children'
The opposition handed over the petition on 2 May. It said it had gathered the signatures of 1.85 million voters backing a recall referendum, many more than the 197,000 needed at this initial stage. The CNE said on Friday there were 1.97 million signatures on the list. Mr Maduro's government said there was widespread fraud in the process. It said the names of thousands of dead voters and children were on the petition. More than 10,000 dead voters and more than 3,000 people under the voting age signed the forms, said Ms Lucena. Mr Capriles said the electoral authorities were working alongside the government in order to derail the recall referendum process.
Henrique Capriles at a protest in Caracas
But he urged voters to get ready to comply with the CNE demand and go to government offices to have their identities checked later this month. Another high-profile opposition activist, Lilian Tintori, also tweeted that her signature had been invalidated by the electoral body. Ms Tintori is the wife of jailed opposition leader Leopoldo Lopez, sentenced last year for allegedly inciting violence in anti-government protests. Ms Lucena warned that the process would be immediately suspended until order was restored if there was "any act of violence, trouble or aggression".
Venezuela is in a serious economic crisis, which the opposition blames on mistaken left-wing policies of Mr Maduro and his predecessor, the late Hugo Chavez. The inflation rate is one of the highest in the world and there are long queues outside shops. Mr Maduro says the shortage of goods is the result of an economic war waged by the country's elite against his government. He defeated Mr Capriles in a tight election three years ago and was elected for a six-year term.
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