Venezuela's National Assembly has re-elected Diosdado Cabello as speaker. He is a close ally of ailing President Hugo Chavez and could take over as caretaker leader if Chavez steps down or dies.
Cabello promised to defend what he called the Chavez revolution when he was sworn in on Saturday.
The president's allies hold a majority in the Assembly and all of its leadership positions. Cabello could become caretaker president until a new election is held.
Chavez is in Cuba for treatment of cancer in his pelvic area. He has not been seen in public in nearly a month. His exact form of cancer and condition are unknown.
Chavez won re-election in October. Vice President Nicolas Maduro said if Chavez is unable to attend his inauguration this coming Thursday before the National Assembly, Chavez could be sworn in later by the Supreme Court.
Opposition leaders argue that the president's inability to take the oath of office on the constitutionally-required date of January 10 would mean he is stepping down.
Some legal experts note that the constitution allows the Supreme Court to swear in the president without mentioning a specific date.
Information Minister Ernesto Villegas said Thursday the president has developed a lung infection that has caused a "breathing insufficiency," which requires him to strictly comply with medical treatment. Earlier this week, Maduro described the president's condition as "delicate."
Some information for this report was provided by AP, AFP and Reuters.