Venezuelan Vice President Nicolas Maduro listens to National Assembly President Diosdado Cabello speak during the assembly inauguration in Caracas, Jan. 5, 2013 REUTERS

Venezuelan President Hugo Chavez’s staunch ally Diosdado Cabello was re-elected as head of the National Assembly Saturday, and he could become the caretaker president if Chavez cannot be sworn in for his new term Thursday.

Opposition politicians and commentators have insisted that if Chavez is not in Venezuela to be sworn in on the scheduled Jan. 10 date, a new election will be required to be held within 30 days.

The 58-year-old socialist leader, who won re-election to a third term Oct. 7, has not been seen or heard in public since he underwent his fourth cancer surgery in Havana on Dec. 11.

“The president will continue being president beyond Jan. 10; nobody should have any doubt about that,” Cabello said after his election, accusing the opposition of fomenting a “coup d’etat,” Agence France-Presse reported.

“We will never defraud the people and we will get on our knees to defend the proposal made by Comandante Chavez, I swear it,” Cabello said as he took his oath of office.

Vice President Nicolas Maduro called the Chavez swearing-in ceremony a “formality” and said he too would stay on in office without taking any oath until there was an opportunity to do so.

"The formality of his swearing-in can be resolved in the Supreme Court," he said. "The president right now is president."

If Chavez had to step down, or die, Cabello would take over the running of the country as Assembly president and a new election would be organized within 30 days.

Maduro, whom Chavez named as his successor, would be the ruling Socialist Party candidate.

In the weeks following the surgery, the government said Chavez had suffered post-operatory complications including unexpected bleeding and a lung infection, but offered few details about his actual condition.

Chavez had undergone three surgeries in less than a year and two sessions of radiation treatments before the presidential election and declared in May that he had beaten the disease. But details of Chavez's ailment as well as the type of cancer he is suffering from are still not known.

Attorney General Cilia Flores had earlier said that the constitution allowed the inauguration date to be postponed, stressing that Chavez was still Venezuela’s president who had been re-elected.