Venezuelan opposition leader Juan Guaido's designated ambassador to Costa Rica has taken control of Venezuela's embassy in the country, triggering criticism from the Costa Rican government for not waiting.

On February 15, the Costa Rican government gave Venezuelan President Nicolas Maduro's representatives 60 days to leave the country.

Costa Rican President Carlos Alvarado has joined the United States and a long list of governments in Latin America and Europe in recognising Guaido, who assumed the interim presidency after declaring Maduro's re-election illegitimate.

Maria Faria, Guaido's representative in Costa Rica, took possession of the embassy early on Wednesday.

"We have come to the embassy to move forward with the transition process," Faria's office said in a statement.

The office said Faria was working with a team of auditors and legal advisers to ensure an orderly transition. It was not immediately clear how her team obtained access to the embassy.

Despite recognising Faria as Venezuela's legitimate ambassador, the Costa Rican foreign ministry criticized her for taking possession of the embassy before the deadline, saying it would send a diplomatic note.

Maduro's foreign minister, Jorge Arreaza, also criticised the move.

"What thieves, this morning a group of strangers entered the headquarters of the Venezuelan embassy in Costa Rica," he wrote in a post on Twitter.