CARACAS -Venezuelan President Hugo Chavez rallied a crowd of thousands, vowing to win a "battle for life" after undergoing cancer surgery.
Chavez addressed the crowd from a balcony of the presidential palace just hours after his surprise return from Cuba.
The Venezuelan president thanked Fidel Castro, saying that the veteran leader has been practically his "medical chief" while recovering in Cuba.
Chavez told the crowd he will "win this battle for life."
Chavez spoke strongly but was thinner and paler than usual. He wore the red beret from his days as an army paratroop commander.
Chavez returned from Cuba on Monday as the country was preparing to celebrate the 200th anniversary of its independence from Spain.
Chavez's surprise return from Cuba after cancer treatment was a classic maneuver for a president who excels at showmanship. It's also likely to give him a political boost as supporters rally around their ailing leader.
The 56-year-old president projected a strong, vibrant image as he stepped off a plane early Monday. Smiling, he hugged his vice president, broke into song and later raised a fist in triumph.
"It's the beginning of my return!" he declared.
That afternoon, he rallied thousands of supporters from a balcony of the presidential palace, telling them: "We will also win this battle for life."
Wearing fatigues and the red beret of his army days, Chavez revealed that he had been in intensive care in Cuba and held up a crucifix. "Christ is with us," he said.
The crowd chanted: "Oh, no! Chavez won't go!"
Despite the confident image, doubts about his future re-emerged as he suggested later in the day that he still isn't ready for a full comeback.
He told state television by telephone that he doesn't expect to attend celebrations Tuesday marking the 200th anniversary of Venezuela's independence from Spain. Normally, Chavez would be front and center at the patriotic event.
Still, for a president who knows how to command attention, his surprise return was signature Chavez and sent a powerful message that he remains in control. During nearly a month in Cuba, uncertainty has swirled in Venezuela, both about how sick he is and what would happen if cancer were to force him from power.
The long-term political impacts of fighting cancer for a leader who thrives on the spotlight remain unclear. But Chavez will likely play up his plight to rally his movement as he looks ahead to 2012 elections, in which his allies say they are convinced he will still be their candidate.
Unanswered questions about Chavez's health abound. He has said he underwent surgery to remove a cancerous tumor, and his foreign minister said it was extracted from the same part of the "pelvic region" where Chavez had an abscess removed in Cuba on June 11. Chavez hasn't said what type of cancer is involved nor whether he is receiving chemotherapy, radiation or another treatment.
Based on Chavez's account, medical experts said it's most likely he has colorectal cancer, but Chavez has not confirmed that.
Many Chavez supporters were thrilled just to have him back Monday, and hundreds celebrated in the Plaza Bolivar in downtown Caracas, holding pictures of the president and chanting "Viva Chavez!" and "He's back!"
Elsa Gonzalez, a 61-year-old building maintenance worker, said she had stopped cooking breakfast when she saw Chavez on TV at the Caracas airport.
"I shouted with excitement," she said, teary-eyed as she joined the revelers in the plaza. "God is going to lay his hands on his body and is going to heal him completely."
Vice President Elias Jaua denied that Chavez's socialist-inspired Bolivarian Revolution movement is threatened and said Chavez was back in the presidential palace. He was scheduled to address supporters from the balcony later in the day.
"He doesn't need to go to the hospital at this time," Jaua said.
Chavez's opponents have criticized the lack of details about his illness.
Leading opposition lawmaker Alfonso Marquina said Chavez's return puts an end to the "irregular situation" of having a president governing from Cuba, but he said much has yet to be explained.
"We don't know exactly what the president's illness is, what treatment he needs and what consequences this treatment will bring," Marquina told The Associated Press in a telephone interview. "What we demand is greater responsibility, no only on the president's part but by all of those high in the government to inform the Venezuelan people properly about the president's real situation."
Chavez has been dominant in Venezuela during more than 12 years in office, and his absence created a void that he clearly wanted to fill.
Ever the political survivor, Chavez's many returns have historically helped him energize his base. Nearly a decade ago, Chavez bounced back in triumph after a 2002 coup briefly ousted him. A decade earlier, when he led his own failed coup in 1992, he said his objectives had not been reached "for now" — a hint of the come-from-behind presidential bid that would sweep him to power.
Chavez returned Monday to a city of freshly painted murals bearing his face and those of the country's 19th-century independence heroes. Yellow, blue and red Venezuelan flags were everywhere downtown, fluttering from lamp posts and over doorways under sunny skies.
The mood among Chavez's supporters was festive. Some acknowledged Chavez faces an uncertain future but said they felt hopeful and relieved, especially after seeing him looking much healthier than he did on TV several days ago.
"If that illness is attacked in time, people get through it," said Xioraima Garcia, a 56-year-old lawyer who came to the plaza to celebrate with the crowd.
Asked how she thinks the situation will affect Chavez politically, she said: "What he's going through has strengthened him more."
Jaua, Foreign Minister Nicolas Maduro and other confidants have stepped up their appearances in Chavez's absence, insisting they remained unified. Chavez's elder brother, Adan, also has taken on a higher profile, at one point threatening armed struggle to continue the president's socialist revolution.
With his return, Chavez has the potential to fill that gap, but political observers will be watching closely to see how often he appears in public, whether he has the stamina to keep up a full schedule, and whether he might be quietly making plans to throw his support behind any of his allies and potential heirs.
Adam Isacson, an analyst at the think tank the Washington Office on Latin America, said Chavez should enjoy a boost for now.
"Hugo Chavez's illness will generate a lot of sympathy for him," Isacson said, adding that it's similar to what Argentine President Cristina Fernandez enjoyed in her poll ratings after her husband's death.
"It is already moving Venezuela's political debate away from themes that don't work to the president's advantage, like crime, power shortages, the economy, and concentration of power in the presidency," Isacson said. "On the other hand, it also moves the debate in directions that Chavez would not want to see it go. For the first time in years, Venezuelans are thinking about what a post-Chavez era might look like. This raises concerns about the lack of an heir-apparent."
Chavez appeared eager to counter such doubts.
"Here I am, at home and very happy!" Chavez said in a message on Twitter sent Monday morning. "Good morning, my beloved Venezuela!"
He went to Cuba on June 8 for what ostensibly was a previously scheduled visit. Chavez has said he underwent an initial operation June 11 to have a pelvic abscess removed.
After an 18-day silence, a video was shown Thursday in which a thinner, visibly weakened Chavez said he had undergone a second surgery to remove a cancerous, abscessed tumor.
While Chavez sang and embraced well-wishers at Caracas' airport about 2 a.m. local time, he was not shown ascending the airplane's stairs in Cuba or descending them in Venezuela.
At the Caracas airport, he raised a fist as he held up a newspaper showing the Venezuelan soccer team's better-than-expected performance Sunday against Brazil.
He later told Venezuela state television he didn't plan to attend widely anticipated bicentennial celebrations Tuesday, which include a military parade.
"I don't think I can accompany you in the official acts tomorrow, but I am here and will be with all of you from my command post in the heart of Caracas," Chavez said.
He added that he planned to consult with doctors before meeting with his government.
"I just finished checking the medical schedule, before anything," Chavez said. He said his medical care would come "before anything.".
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