In this picture provided Tuesday, Dec. 11, 2012 by Cuba's state newspaper Granma, Cuba's President Raul Castro, right, receives Venezuela's President Hugo Chavez at the Jose Marti International airport in Havana, Cuba, Monday, Dec. 10, 2012. Chavez arrived in Cuba on Monday for a fourth cancer-related operation after designating the vice president as his political heir. (AP Photo/Granma)
CARACAS, Venezuela (AP) — Venezuelan President Hugo Chavez was preparing to undergo a new cancer surgery on Tuesday in Cuba, his government said, after his illness reappeared despite a year and a half of surgeries and treatments.
Venezuela's government said in a statement that Chavez's medical team had begun "pre-operative protocol" to carry out the surgery on Tuesday.
"His medical team has transmitted its optimism about the success of this operation," the government said in the statement, which Information Minister Ernesto Villegas read on television.
He said the government called on Venezuelans to "remain united in prayer."
Venezuela released the statement after Ecuadorean President Rafael Correa said Chavez was undergoing the operation "at this moment."
"It's a very delicate operation," Correa said at an event in the Ecuadorean city of Tulcan.
"He's passing through one of the hardest moments of his life. Our heart and our solidarity are with a historic president," he said. Correa, a close ally of the socialist leader, traveled to Cuba on Monday to meet with Chavez.
The Venezuelan president announced on Saturday that he needed to undergo a fourth cancer-related surgery after tests showed that "some malignant cells" had reappeared in the same area in his pelvic region where tumors were previously removed.
Chavez also said for the first time that if his illness cuts short his presidency, Vice President Nicolas Maduro should take his place and be elected president to continue on with his leftist movement.
In recent days, groups of supporters have gathered to pray for Chavez in Venezuela and elsewhere. In Bolivia, American actor Sean Penn joined a candlelight vigil on Monday wearing a track suit emblazoned with the colors of Venezuela's flag, just like one that Chavez has worn.
"He is one of the most important forces we've had on this planet. And I will wish him nothing but that great strength he has shown over and over again," Penn told a crowd at the vigil, his voice quavering with emotion.
Penn called Chavez "inspiring."
Chavez first announced he had been diagnosed with cancer in June 2011. He underwent a surgery for a pelvic abscess, and then had a baseball-sized tumor removed from his pelvic area. In February, he underwent another surgery when a tumor reappeared in the same area.
He has also undergone months of chemotherapy and radiation treatments. Throughout his treatments in Cuba, Chavez has kept secret some details of his illness, including the exact location and type of the tumors.
Chavez had previously said in July that tests showed he was cancer-free, and he was re-elected in October to another six-year term. He said over the weekend that recent tests in Cuba had again found cancerous cells.