Chavez would not be able to attend the scheduled inauguration in a letter to National Assembly President Diosdado Cabello, which he announced he had received on Tuesday.

The government called for the socialist president's supporters to gather for a demonstration at the presidential palace Thursday, and said that some foreign leaders were coming to visit. Bolivian President Evo Morales and Uruguayan President Jose Mujica confirmed they will attend.

Chavez said before his operation that if he were unable to continue on as president, Maduro should take his place and run in an election to replace him. Speculation that his illness might be entering its final stages grew on Tuesday when the proposal for a postponement came in a letter signed by Maduro, not Chavez.

The government said earlier this week thatChavez was in a "stable situation" receiving treatment due to a severe respiratory infection. The government has said he is coping with "respiratory deficiency," but hasn't said how severe it is.

The stances of the government and the Supreme Court have been criticized by legal scholars such as Vicente Gonzalez de la Vega, a law professor at Central University of Venezuela, who said the Supreme Court has effectively consummated a sort of "coup d'etat."

"How can it say that the president isn't absent and he's in his duties when he can't even sign a letter?" Gonzalez told the AP.

Francisco Madrid, a businessman and opposition supporter, called the Supreme Court's decision "shameful."

"It's proof that all branches of the state respond to the government's interests," Madrid said while walking in downtown Caracas.