A mustachioed former bus driver who rose to become Venezuela's top diplomat has emerged as the vice presidential pick of President Hugo Chavez as the leftist leader prepares to launch a six-year term following two cancer operations.

Nicolas Maduro has shown unflagging loyalty and has maintained close ties to Chavez's allies in Cuba while becoming the president's principal spokesman and an influential leader within his socialist party.

Chavez announced Maduro as his new vice president on Wednesday, three days after winning re-election.

Eduardo Gamarra is a Latin American studies professor at Florida International University in Miami.

He says Chavez's choice of Maduro was expected, in his words, because "he appears strong, he's charismatic to some, and he is loyal."