A Venezuelan minister on Wednesday said cancer-stricken President Hugo Chavez was in a "delicate" but stable condition following a fourth operation in Cuba.
"The medical team explains to us that the condition of President Chavez remains stable with delicate symptoms," Science Minister Jorge Arreaza said on Twitter from Havana.
Chavez' brother Adan Chavez, who is the governor of the state of Barinas, has also arrived in the Cuban capital, Arreaza said.
Vice-President Nicolas Maduro, whom Chavez has appointed as his successor, is also in Havana with the president, according to Arreaza.
Chavez underwent his fourth operation for cancer in Cuba on December 11. Bolivian President Evo Morales, who visited Chavez recently, later described his condition as "very worrying."
Venezuelan medical doctor Jose Rafael Marquina, who said he had talked to reliable sources, estimated there to be a 90-per-cent chance that Chavez would not survive until he is due to be sworn in for a new term on January 10.
The Venezuelan opposition alliance Democratic Unity Roundtable (MUD) accuses the authorities of only giving "insufficient" information on Chavez' health, with the secrecy of the government fostering uncertainty and rumours, MUD executive secretary Ramon Guillermo Aveledo said.
Meanwhile in Washington, US State Department spokeswoman Victoria Nuland said the United States expected Venezuela to stage "transparent, democratic, free and fair" elections in case Chavez could not take office.