Venezuela's chief prosecutor ordered the arrest of the former head of the country's state oil company on Thursday, accusing him of bankrupting the downtrodden country's primary source of income.

Officials also announced that Venezuela is expelling the Spanish ambassador in a move that further isolates the Latin American country from the international community.

Rafael Ramirez, who recently resigned as Venezuela's United Nations ambassador, is wanted on suspicion of money laundering and embezzlement related to the state oil company, PDVSA, said Attorney General Tarek William Saab.

Saab said he's preparing to ask the international police agency Interpol to issue a "red alert" for the arrest. He called Ramirez the "father of corruption" at the oil company.

"You used to make millionaires of your family members," Saab said on state television. "Mr. Ramirez, we inform you that you are cited by this ministry."

Ramirez's associates have been a target of the Saab-led crackdown on corruption at the troubled state oil company that began late last year. Dozens of officials have been arrested, including two former oil ministers and Ramirez's cousin, Diego Salazar.

Salazar has been arrested on suspicion of helping siphon off $1.6 billion to banks in the European principality of Andorra.

Ramirez, who ran PDVSA for more than a decade, resigned from his U.N. post in early December on orders from President Nicolas Maduro.

Ramirez has denied taking part in any corruption scheme and has not made his whereabouts public after leaving the New York. On Sunday, he published an article asked Venezuelan officials for safe passage to participate in primaries for the presidential elections this year as a candidate of the socialist ruling party.

Meanwhile, Minister of Foreign Affairs Jorge Arreaza announced earlier Thursday that Venezuela is declaring Spanish ambassador Jesus Silva Fernandez a persona non grata.

Arreaza accused Spain of "imperialist and supremacist" meddling in its affairs.

The action came days after Spain and several countries in the European Union imposed economic and travel sanctions on seven senior Venezuelan officials accused of human rights abuses or breaching the rule of law.

Venezuela was once a Spanish colony and Spain remains a major trading partner for the region. Many Venezuelans have fled to Spain during their country's deepening crisis.

Venezuela in December expelled top diplomats from Canada and Brazil on similar grounds.

Spanish Foreign Minister Alfonso Dastis said his country will respond with "proportionate reciprocal measures," and said a range of possibilities would be discussed at the Spanish government's weekly Cabinet meeting on Friday.