CARACAS, Venezuela: An opponent of Hugo Chavez alleged Sunday that conflicts are brewing within Venezuela's ruling party and argued that alleged differences between the president's close confidants have prompted them to seek to postpone the socialist leader's inauguration.

Opposition lawmaker Julio Borges told a news conference Sunday that a rivalry between Vice President Nicolas Maduro and National Assembly President Diosdado Cabello was behind their comments that Chavez's swearing-in ceremony on Thursday could be postponed if necessary. Chavez has not been able to return to Venezuela from Cuba following a Dec. 11 operation, his fourth surgery for an undisclosed type of pelvic cancer.

"While the president is sick in Havana, they have a power conflict," Borges said. "That's why they are engendering this violation of the constitution."

The Venezuelan Constitution states the presidential oath should be taken before lawmakers in the National Assembly on Jan. 10, this Thursday. But it says the president may also take the oath before the Supreme Court if the president is unable to be sworn in before the assembly.

The government revealed last week that Chavez is fighting a severe lung infection and receiving treatment for "respiratory deficiency."

There have been no public signs of friction between Maduro and Cabello, who appeared side by side waving to supporters after a legislative session on Saturday. The two men have repeatedly rejected speculation they are at odds and have vowed to remain united.

"Come here, Nicolas. You're my brother, friend. They don't understand that," Cabello said, hugging Maduro before the crowd outside the assembly.

Borges, however, alleged that the two men were putting on a show.

"That big hug between Nicolas Maduro and Diosdado Cabello was set up to reflect unity that does not exist," he said.

In a statement posted Sunday on Twitter, former vice president and prominent ruling party member Elias Jaua stressed the need to work together.

"We are obligated ... to remain united in this and any other situation," Jaua wrote.

Opposition leaders have argued that the inauguration should occur Thursday, when one presidential term ends and another begins. They have demanded more information about Chavez's condition and have said that if Chavez can't make it back to Caracas by Thursday, the president of the National Assembly should take over provisionally.

But Attorney General Cilia Flores on Sunday rebuffed that position by opposition leaders, saying in a televised interview that if Chavez "can't be sworn in before the National Assembly, he will do it before the Supreme Court." Flores, who recently was among officials who met with Chavez in Cuba, backed arguments by Maduro and Cabello that the date specified in the constitution for a president to take office is not a firm deadline in this case.

"Here we have a president who was re-elected, who is in possession of his post," Flores said in comments reported by the state-run Venezuelan News Agency. "The president even has his presidential sash already."

Earlier Sunday, Venezuelan athletes who support Chavez prayed for the socialist leader's recovery.

Formula One driver Pastor Maldonado, IndyCar Series driver Ernesto Jose Viso and others attended a Mass at a church in downtown Caracas. Athletes wearing jackets with the colors and stars of Venezuela's flag stood before an altar, solemnly reciting prayers.

Maldonado, who is sponsored by Venezuela's state oil company Petroleos de Venezuela SA, expressed confidence that Chavez would soon recover and return to Venezuela.

The F1 driver voiced hope that "very soon he's here with all of us."

Viso said he and millions of other Chavez supporters have "much faith that he's recovering."

"We wish him the best," Viso said.