By Brian Ellsworth and Deisy Buitrago
CARACAS (Reuters) - Allies of Venezuela's ailing President Hugo Chavez insisted on Monday he was still leading the OPEC nation despite a week of silence from the usually loquacious leader whose battle with cancer has overshadowed his reelection bid.
Chavez's normally ubiquitous media presence has slowed to a trickle of Tweets. He has not made any live contact with state media in the week since a public appearance last Monday before leaving for Cuba to receive treatment.
His absence has fanned criticism that he is no longer properly running the country and spurred unprecedented talk of a successor to the former soldier, who during 13 years in power has avoided cultivating a protege who could replace him.
"The president, while still receiving treatment, continues to govern," said ruling party stalwart Aristobulo Isturiz.
"For (the opposition), the issue of the president's health is not humanitarian but rather electoral because their only possibility of victory comes from Chavez's illness."
Chavez's health is treated as a state secret.
He has had three operations since last June, including one that removed a baseball-sized tumor. But government leaders have refused to divulge details about his condition.
He is supposed to have completed the last of five radiotherapy sessions, but the unusual silence has spurred speculation his condition may be getting worse, possibly fatal.
TRANSITION TALK GROWS
The recent creation of a Council of State, charged with advising the president on policy issues, has been interpreted by analysts and some opposition activists as a transition agency that could ease the way toward a post-Chavez Venezuela.
Party leaders deny this, insisting he is their only candidate and assuring voters he will sweep opposition rival Henrique Capriles in the upcoming October 7 vote.
"It is not a transition (committee) and there will be no transition," said a long-faced Vice President Elias Jaua on Sunday in a ceremony filled with Chavez supporters clad in signature red shirts chanting party slogans.
"There will be elections, re-election and a new term for Hugo Chavez."
Allies seen as potential replacements for him if he cannot run in the October 7 vote include Jaua, foreign minister Nicolas Maduro, and National Assembly President Diosdado Cabello.
Chavez's two daughters, who have no political experience but frequently appear with him in public, are seen as potential stand-ins who could command respect from supporters and allies.
"There is no way to know the likelihood of any given scenario without serious information about Chavez's health," said local pollster and analyst Luis Vicente Leon via Twitter.
"But one thing is clear: Chavez will be the candidate, dead or alive. Even if Chavez is physically absent, the campaign will be full of his symbols, photos, messages and missions."
TWEETS FROM HAVANA
In an attempt to show government as normal, the foreign ministry sent a statement on Sunday conveying Chavez's congratulations to France's Francois Hollande on his presidential election victory.
But Chavez, who has spent most of the last six weeks in Havana, has only been seen once live in public since mid-April.
He ended that short address on Monday choking on his words, with tears in his eyes, in sharp contrast to his triumphant speech to Congress in January that stretched for nine hours.
His recent Twitter comments have been limited to greetings to allies and promises of state funding for arcane projects ranging from fixing broken elevators to boosting sugar cane production.
One source close to the government said Chavez's health has deteriorated considerably with the radiotherapy. He has been in intense pain and is unable to walk, requiring him to use a wheelchair, the source told Reuters.
"There is great anxiety over what is coming," the source said.
Financial markets have reacted positively to the news of his illness, with the country's bonds rallying broadly on the possibility of a more market-friendly government.
Chavez's oil-financed social welfare crusade has made him immensely popular among the country's poor, who have handed him repeated ballot box victories since he first won office in 1998.
Opposition leaders, who have avoided directly commenting on his illness, describe him as a doctrinaire autocrat whose steady expansion of the state has weakened the economy and left Venezuelans dependent on state handouts.
(Additional reporting by Eyanir Chinea; editing by Andrew Cawthorne and Todd Eastham)