Venezuela's top opposition leader on Tuesday urged the Supreme Court to rule on whether cancer-stricken President Hugo Chavez's re-inauguration can be postponed, as his government argues.

I do not know what the judges of the Supreme Court are waiting for. Right now in Venezuela, without any doubt whatsoever, a constitutional conflict has arisen," Henrique Capriles said. Chavez is scheduled to take the oath of office on Thursday following his October re-election win. But he is recovering from cancer surgery in Cuba, his fourth operation in 18 months, and it not clear he will make it to the ceremony in Caracas.

The government says the swearing is a mere formality that can be delayed, but the opposition says the constitution must be respected.The charter says new elections must be held within 30 days if the president-elect dies or is permanently incapacitated either before he takes office or in the first four years of his six-year term.

"There must be a response from our institutions in the face of this conflict," said Capriles, who lost to Chavez in the October vote but gave him a run for his money.Capriles also urged Latin American leaders to stay away from a pro-Chavez rally convened by the government for Thursday in place of the inauguration.