Milk has become a luxury item in Cuba since Soviet subsidies dried up in the 1990s, leading to a shortage of quality animal feed and a disastrous decline in milk yields. Fidel Castro's government hopes to solve the problem by "resurrecting" a bovine hero of the Communist revolution - 17 years after its death.

The daily milk yield of a cow called Ubre Blanca (White Udder) astonished and delighted Communist Party officials in the early 1980s. In 1982 it produced 110 litres of milk in a single day - four times the average - and instantly became a legend throughout Cuba.

In the same way that the Soviet Union mythologised Alexei Stakhanov, the miner who was reputed to have overfilled his quota by 1400 per cent when he hewed 102 tonnes of coal in a day, Ubre Blanca received front page treatment in Granma, the Cuban equivalent of Pravda.

President Castro visited its farm, appearing on television as he gently stroked the hide of the finest member of the country's workforce. No bovine in the United States, it was pointed out, could come close to matching White Udder's output.

When the cow died in 1985, President Castro commissioned a marble statue, which still stands in the rural town of Nuevo Gerona, where White Udder once grazed. Taxidermists stuffed her and moving obituaries appeared in Granma. "She gave her all for the people," said Pastor Ponce, an agronomist.

Then, Cuba's scientists began devoting all their energies towards achieving a second White Udder, using frozen tissue and eggs taken from the cow while it was alive.

Now, Dr Jose Morales, the head of the White Udder cloning project at the Havana Centre for Genetic Engineering and Biotechnology, is confident a breakthrough is imminent. "We're very close," he said. "We have big things coming. This project is very important to Commandante Castro."

Other Cubans are more sceptical about their leader's big idea. Andres Molina Valdes, a researcher with the Cuban Institute of Animal Science, said it would take more than a second White Udder to solve the problems that had plagued the dairy industry since the revolution.

"So we clone White Udder. And then what?" said Mr Valdes. "Cuba's problem is not a single cow; it's the tens of thousands of animals which produce food for the country. Cows are producing much less than they should do and they're also dying much earlier than they should do. The way in which we're going about this, we're never going to improve things."

Exasperated by the Cuban Government's sentimental attachment to the long-dead White Udder, Mr Valdes has asked for asylum in the US, where he hopes that scientific research will not be as "politicised".