CARACAS, Venezuela - Venezuelan President Hugo Chavez announced Saturday night that his cancer has returned and that he will undergo another surgery in Cuba.

Chavez, who won re-election on Oct. 7, also said for the first time that if his health were to worsen, his successor would be Vice-President Nicolas Maduro.

"We should guarantee the advance of the Bolivarian Revolution," Chavez said on television, seated at the presidential palace with Maduro and other aides.

The president said that tests had shown a return of some cancerous cells and that he would return to Cuba on Sunday for the surgery, his third operation to remove cancerous tissue in about a year and a half.