Venezuela's vice president said Hugo Chavez's new term as head of state will begin on Jan. 10 and that if the ailing leader is not able to take the oath of office before the National Assembly on that date he can be sworn in at a later time by the Supreme Court.

Nicolas Maduro made the remarks after opposition leaders said the head of the National Assembly - controlled by Chavez allies - must take over as interim president and new elections must be called if the socialist leader cannot return to Venezuela to be sworn in on Thursday.

Maduro said Friday that the constitution allows for the "formality" of the swearing-in ceremony to be "resolved before the Supreme Court at the time (the high court) deems in coordination with the president."

The 58-year-old Chavez, who remains hospitalized in Cuba more than three weeks after his latest cancer surgery, is experiencing respiratory deficiency caused by a "severe" lung infection, government officials said this week.

"Following the delicate Dec. 11 surgery, comandante Chavez has faced complications stemming from a severe lung infection," Communications Minister Ernesto Villegas said in a statement on Venezuelan television and radio Thursday night.

The president was first diagnosed with cancer after complaining of pain in his pelvic region during a June 2011 official visit to Cuba. Since then, the former paratrooper has undergone four surgical procedures and courses of chemotherapy and radiation.

Amid intensifying speculation about Chavez's condition, the U.S. State Department said Wednesday that it expects Caracas to pursue a transition consistent with the Venezuelan Constitution should the president become unable to perform his duties.

U.S. Assistant Secretary of State for Western Hemisphere Affairs Roberta Jacobson held talks in November with Maduro in a bid to normalize bilateral relations, a U.S. official, who spoke on condition of anonymity, told Efe Friday.

According to an article published this week in the Miami daily El Nuevo Herald and deemed reliable by the U.S. official, Jacobson proposed to Maduro that the two countries take a series of "intermediate steps" - related to energy cooperation and joint efforts against drug trafficking and terrorism - before the countries' respective ambassadors are returned to their posts.

The diplomatic spat in late 2010 erupted after Caracas refused to welcome the United States' proposed envoy to Venezuela, Larry Palmer, and Washington responded by revoking the visa of Venezuelan Ambassador to the United States Bernardo Alvarez.

Chavez, in power since 1999 and re-elected in October to another six-year term, has repeatedly accused Washington of wanting to overthrow his government to gain control of massive oil and natural-gas reserves in Venezuela.

Despite the frequent diplomatic spats, Venezuelan remains a key oil supplier to the United States. EFE