The United States and Cuba do not have full diplomatic relations, and the US government has maintained an economic embargo on the only one-party communist state in the Americas for decades.

The bipartisan delegation that arrived here Friday has been pressing for the US government to lift the embargo and resume a dialogue with Havana, a move opposed by the Republican administration of George W. Bush unless Cuba takes steps toward democracy.

Jeff Flake, an Arizona Republican, was co-leading the delegation with William Delahunt, a Massachusetts Democrat.

Both are members of the House of Representatives Committee on Foreign Relations and leading members of the Cuba Working Group, which aims to foster better political, economic and cultural ties.

The American delegation met Friday with Ricardo Alarcon, president of Cuba's National Assembly and the top official for US affairs.

Among Saturday's round of events was a reception with Foreign Minister Felipe Perez Roque, and meetings with central bank governor Francisco Soberon and Basic Industries Minister Yadira Garcia, an influential member of the Politburo of Cuba's Communist Party.

Authorities did not rule out a meeting with interim leader Raul Castro or Vice President Carlos Lage, organizers of the visit said privately.

Cuba's media, all under state control, did not announce the visit prior to the arrival of the American delegation, who traveled on a US military jet, US sources said.

Raul Castro, who is also the defense minister, has reached out to Washington more actively in his four months in interim power than his brother did in more than four decades as Cuba's leader.

On December 2, at a military parade at which Fidel Castro did not appear, Raul Castro called for negotiations between the two countries.

But the United States so far has said it is not interested in negotiating until there is a sign of political liberalization in Cuba.

Wednesday, the top US diplomat for Latin America, Tom Shannon, indicated that Washington had yet to see any reformers in the Cuban government. But he did not flatly rule out dialogue with Havana.

Shannon said any US engagement with Cuba must be "part of a change process that facilitates a democratic transition."

Fidel Castro has not been seen in public since July 26, the day before his intestinal surgery.

Castro was informed of the details of the meeting led by Vice President Carlos Lage and assembly speaker Ricardo Alarcon, Granma added.

The news came after US Director of National Intelligence John Negroponte told the Washington Post that Castro was very ill and close to death.

"Everything we see indicates it will not be much longer, ... months, not years," the Post quoted Negroponte as saying Friday. Negroponte gave no details in the interview to back up his statement.

Later Friday, Castro's closest ally, Venezuelan President Hugo Chavez, said in his country that he had spoken twice with Fidel by phone on Thursday.

"I saw in the press there are some reports Fidel is dying. ... He seemed very well to me yesterday, and, well, someday all of us will die physically, but one thing that is true: ... Fidel does not have cancer. I am well informed," Chavez said.

Castro, 80, handed over the reins of power on July 31 to his brother Raul, the army chief. Fidel Castro underwent intestinal surgery in July and details of his condition are guarded as state secrets.

Raul Castro, 75, has reached out to the United States more actively than has his brother in the past four months, calling for negotiations.

The US government has said it would not accept a Castro dynasty, and has called for free elections in Cuba.

But on Friday, a bipartisan group of 10 US lawmakers, all supporters of easing US sanctions on Cuba, traveled to Havana to meet with top Cuban officials. The largest US legislative delegation ever to visit communist-ruled Cuba, it met late Friday with Alarcon and was to meet with other top Cuban officials.

The United States and Cuba do not have full diplomatic relations, and Washington has for decades maintained an economic embargo on the only one-party communist state in the Americas.

Rumors about Fidel Castro's health have gathered force since he sat out a December 2 military parade in Havana honoring his 80th birthday.

Britain's The Independent has reported that Castro is ailing from cancer, has refused chemotherapy and could die before Christmas (December 25).

On Wednesday, the top US diplomat for Latin America, Tom Shannon, indicated that the United States had yet to find a reformer in the communist Cuban government, but did not flatly rule out dialogue with Havana in the context of a political opening.

"Once (Fidel Castro) goes, the successor government is going to have to chart out some kind of path into the future. There are no clear signals of what that path is going to be," said Shannon, the US assistant secretary of state for the Western Hemisphere.

"We don't see any significant possibility of change of any kind until Fidel is gone," he added.

Fidel Castro has not been seen in public since July 26, the day before his surgery, though he has appeared in videotaped visits in his hospital room.

Mr Castro's medical condition has been treated as a state secret since he underwent surgery for intestinal bleeding in late July and temporarily ceded power to his younger brother, Raul Castro. He has not been seen in public since July 26.

Cuban officials have repeatedly insisted that the elder Castro is recovering, and the vice-president, Carlos Lage, previously denied reports that the president was suffering from stomach cancer. But officials have not publicly denied rumours that he could have another type of cancer or some other terminal illness.

US officials, meanwhile, say they believe Mr Castro suffers from some kind of inoperable cancer and won't live to the end of 2007.