After weeks of speculation over the state of his health, Hugo Chávez has revealed that he has had surgery to remove a cancerous tumour. In his first video appearance since being hospitalised in Cuba, Chávez said doctors had removed "cancerous cells" from his body. "This [is] the new battle that life has placed before us," he said.

In an uncharacteristically short speech, he ruefully reflected, "I neglected my health and I was reluctant to have medical check ups. It was a fundamental mistake for a revolutionary."

The Venezuelan president was rushed to hospital on 10 June after suffering abdominal pain while in a meeting with Fidel Castro. He later underwent emergency pelvic surgery and, as we now know, a second operation to remove a tumour.

It's still unclear when Chávez will return to Venezuela and the news has dismayed his supporters, who were confident that he would win re-election next year. The opposition is arguing that it is unconstitutional for Chávez to govern the country from abroad. Others have criticised him for initially denying claims that he had been diagnosed with cancer.

But most importantly, as I wrote on Monday, Chávez's absence has highlighted the lack of any obvious successor to his Bolivarian Revolution. Aware of this fact, his supporters are discussing the possibility of a Castro-like succession which would see Chavez's older brother, Adán Chávez, take over the presidency. As today's New York Times notes: "no government figure has occupied the political void created by [Chávez's] absence more assertively than his older brother, Adán Chávez, a physicist whose radical thinking has often been to the left of the president's."

In the meantime, Venezuelan politics remains as polarised as ever. On Saturday, the Vice Foreign Minister, Temir Porras, said: "The only thing that has metastasized is the cancer of the Miami Herald and the rest of the right-wing media."