Cuban leader Fidel Castro missed the opening of the weeklong belated celebration of his 80th birthday, sending an uncharacteristically brief note instead.

BY FRANCES ROBLES

Cuban leader Fidel Castro Tuesday missed the opening event of his 80th birthday celebrations, instead sending a note to a large gathering of supporters in Havana that he was ``in no condition, according to the doctors, to face such a colossal gathering.''

In a brief written statement read aloud to an audience of hundreds of guests at the Karl Marx Theater, Castro said he faced a dilemma: Only the mammoth theater could fit all of the invited guests, yet doctors said he couldn't be around so many people.

''I opted for the variant of speaking to all, using this means,'' said the statement. ``My thought about glory and honor, as expressed by [José] Martí, is well-known, when he said that all [glory and honor] fit inside a grain of corn.''

Castro's note also said the United States' leadership had created a crisis of such magnitude that ``the American people themselves will almost surely not allow him [President Bush] to finish his term.''

He went on to say that he had sent a letter to Venezuelan President Hugo Chávez congratulating him for his efforts to save energy by adopting a Cuban program of issuing power-saving light bulbs.

''We have a duty to save our species,'' Castro said.

The Cuban leader stunned the world almost four months ago by announcing that he had undergone intestinal surgery and temporarily ceded power to his brother Raúl. He also asked that celebrations marking his 80th birthday on Aug. 13 be postponed until Saturday to give him time to recover from surgery.

U.S. officials have said they believe he suffers from terminal cancer, but the Cuban government has steadfastly refused comment on his illness, saying only that he has been recovering. Castro himself has made only infrequent statements since his illness was announced.

More than a dozen missile launchers are standing by and MiG fighter jets are soaring across Havana's skies. Traffic is being diverted and loudspeakers are up at the Plaza of the Revolution.

The festivities to honor Castro began Tuesday night with the ceremony at the Karl Marx Theater. Other activities include a three-day conference that begins today, an art exhibit and a concert Thursday featuring Cuban and Latin American performers like Cubans Silvio Rodríguez and Los Van Van; Cabas, a Colombian pop fusion artist; and Danny Rivera of Puerto Rico.

''Every day, every hour, every minute, the success of this event is more evident,'' organizer Alfredo Vera told the Cuban media.

The largest preparations are being made for a parade Saturday, where 300,000 people are expected. The event will also commemorate the 50th anniversary of the arrival of Castro's yacht Granma, the one used to launch his leftist revolution.

Castro's 700-word note Tuesday, which also stated that ''it is still not known what effect the radiation of thousands of millions of computers and cellphones will have on human beings,'' did not clarify whether he would attend or miss the Saturday event.

Military tanks have been lined up since Sunday to rehearse for the parade, the first of its kind in 10 years. Traffic has been paralyzed, several people contacted in Havana said.

''This is a way to tell people there is power,'' said Martha Beatriz Roque, a dissident in Havana.

``But it's the end of the month, which means above all people are worried about finding food to eat, so these things don't interest them. There will probably be plenty of people there: Anyone whose workplace has been mobilized has to go.''

Attendance at mass marches and rallies in Cuba is generally guaranteed, because the government mobilizes government workplaces, which require their workers to attend.

This week's cultural events were organized by the Guayasamín Foundation, an Ecuadorean group named after the late painter Oswaldo Guayasamín, the first to paint Castro's portrait.

Among those attending are Colombian writer Gabriel García Márquez, Bolivian President Evo Morales, Mexican actress María Rojo, former Ecuadorean President Rodrigo Borja and Argentine ex-soccer star Diego Maradona.