Che Guevara's daughter received a standing ovation after delivering a rousing speech against the US blockade of Cuba.
Aleida Guevara addressed delegates at a Cuba Solidarity Campaign fringe meeting at TUC conference on Monday night. She said: "A lot of damage has been done to our country as a result of this blockade. In public health this blockade is felt very strongly.
Dr Guevara, a paediatrician in Havana, explained how they are unable to treat someone diagnosed with a heart condition because the drug is owned by a US pharmaceutical.
"We will not tolerate the fact that the US government wants to prevent all countries in the world from trading with Cuba," she said.
"Cuba's treatment for lung cancer is the best. We released the world's first lung cancer vaccine but the US won't allow EU countries to buy it."
Dr Guevara stressed the importance of solidarity with Cuba. "It's important we get stronger every day. We need you to be aware of the power you have in your hands, that when the people are united nothing in the world can stop it."
RMT general secretary Bob Crow, one of many speakers at the fringe representing the British trade union movement, said: "Cuba is a beacon because it has gone down a different road and shown that there is a different world out there, a world that does not depend on the size of your wallet. Viva Cuba!"
Aleida Guevara is touring the country speaking in Newcastle tomorrow, Glasgow (September 14) and Oxford (September 19). A candlelit vigil will also be held outside the US embassy in Grosvenor Square, London from 6pm on Tuesday September 18 calling for the Miami Five to be freed.
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