Chávez back in Cuba for oxygen treatment

In a surprise development, Venezuelan President Hugo Chávez traveling to Cuba on Tuesday for "special treatment" to help him in his ongoing recovery from cancer surgery last year.

A notice was read by National Assembly president Diosdado Cabello in a nationwide broadcast, saying that Chávez had asked lawmakers' permission to remain outside the country for an unspecified period. Cabello did not say when Chávez had left for Cuba.

The president, who was re-elected to a fourth term in October, has been out of the public eye for the past two weeks, fueling speculation that his health has deteriorated.

"Six months after I completed the last radiation therapy treatment, it has been recommended that I begin a special treatment consisting of various hyperbaric oxygenation sessions," he said in his letter read by Cabello. "Together with physical therapy, [the treatment] will consolidate the process of strengthening my health."

According to the American Cancer Society's website, hyperbaric oxygenation involves breathing pure oxygen in a pressurized chamber.

The 58-year-old Chávez staged a comeback to run for an unprecedented fourth term after undergoing cancer surgery in June 2011. It has never been disclosed what type of cancer Chávez had, except that it was located in the pelvic area. Chávez has undergone radiation and chemotherapy treatments in Cuba following his surgery.