President Hugo Chavez was in a stable condition in hospital, the Venezuelan government said, without clarifying whether he would be sworn in for a fourth term on Thursday as planned.
The 58-year-old left-wing nationalist leader who was re-elected in October is being treated for cancer in Cuba. Last week he suffered respiratory failure.
Information Minister Ernesto Villegas said Chavez was undergoing "permanent and rigorous" medical treatment and that the government was in constant contact with his doctors and relatives in Havana.
He called on Venezuelans to ignore the "psychological war" being waged "from abroad" to spread rumours about the president's health.
Chavez appointed his deputy, Nicolas Maduro, as his successor prior to undergoing his fourth cancer surgery on December 11.
Maduro has said the president could be sworn in later if he is unable to attend the ceremony, while parliament president Diosdado Cabello said several leaders were expected to arrive in Caracas on Thursday to "visit us and show their solidarity to commander Chavez."
The opposition has called for new elections if Chavez cannot be sworn in on Thursday.