Venezuela's National Assembly has re-elected the ruling party's Diosdado Cabello as its speaker, putting him in line to be caretaker president if Hugo Chavez does not recover from cancer surgery.
Cabello was retained as legislative leader in a vote by a show of hands on Saturday. Chavez's allies hold a majority of the 165 congressional seats.
"We will never defraud the people and we will get on our knees to defend the proposal made by comandante Chavez, I swear it," Cabello said as he took the oath of office.
The vote came as it appeared almost certain that illness will prevent Chavez from being sworn in on January 10 to a new six-year term. Controversial moves by the government have cleared the way for him to retain his powers anyway.
Hundreds of supporters, dressed in the red colour symbolising his socialist revolution, chanted for Chavez outside the National Assembly in a show of unity.
"We are all Chavez! Our comandante will be well! He will return!," they chanted.
If Chavez had to step down, or died, Cabello would take over the running of the country as Assembly president and a new
election would be organised within 30 days. Chavez's heir apparent, Nicolas Maduro, would be the ruling Socialist Party candidate.
Chavez, who is recovering in Cuba from his fourth and most difficult round of cancer surgery, has not been seen in public nor heard from in more than three weeks.
Maduro signalled on Friday that Chavez would not be able to take the oath of office on January 10, a date established by Venezuela's constitution.
Arguing for continuity, Maduro laid out a legal rationale for indefinitely delaying Chavez's swearing-in without him giving up the powers of the presidency, even on a temporary basis.
The country's main opposition coalition insists that Chavez must take at least a temporary leave if his health keeps him from taking the oath on time.
Under the constitution, new elections must be held if the president dies or is permanently incapacitated either before he takes office, or in the first four years of his six-year term.
"There is ongoing debate about the articles of the constitution," Al Jazeera's Teresa Bo, reporting from Caracas, said.
"Whether they will benefit the government or benefit the opposition will be resolved by the National Assembly or Supreme Court - both of which are filled with Chavez loyalists."
"But it is the president of the National Assembly who would become president if something were to happen to Hugo Chavez."
The government said this week that since undergoing surgery last month in Havana the president has developed a "serious pulmonary infection" that has led to a "respiratory insufficiency."
"The official version of what is happening is unsustainable," the head of the main opposition coalition, Ramon Guillermo Aveledo, said.
Aveledo said it would make more sense for the government to acknowledge "the truth" and use it to prepare the country for what is to come. But it "doesn't want to admit that the president is absent".
Chavez, 58, was re-elected on October 7 despite his debilitating battle with cancer and the strongest opposition challenge yet to his rule.