CARACAS: Venezuelan Vice President Nicolas Maduro is to deliver the annual state of the nation address (SONA) to lawmakers on Tuesday in place of cancer-stricken President Hugo Chavez, who is convalescing in Cuba.

Maduro, Chavez’s chosen political heir, will give the speech in accordance with the constitution, because of Chavez’s authorized leave of absence, the first vice president of the National Assembly, Dario Vivas, told Venezuelan radio.

The constitution stipulates that the president “personally” deliver the state of the nation address within 10 days of the swearing-in of the legislature, which took place on January 5.

Chavez, however, underwent a fourth round of cancer surgery more than a month ago in Havana, and he has not been seen or heard from since.

The 58-year-old leftist firebrand was to have been sworn in for a new term on January 10, following his reelection in October, but he was too sick to travel as he battles post-operative complications.

Authorities insist that the Venezuelan constitution allows him to take the oath of office at a later time—a move the country’s Supreme Court said that was constitutional. The opposition has nevertheless cried foul.

On Sunday, Venezuela’s information Minister Ernesto Villegas said that Chavez’s condition was improving, though he still required treatment for “respiratory failure.”

Maduro visited Havana over the weekend and saw Chavez.