Britain bowed to Washington yesterday and banned Cuban star witness René González from attending a landmark inquiry into discredited US prison sentences handed to him and four compatriots.

Cuba solidarity activists confirmed the "unsettling" news hours before he had been scheduled to arrive in London.

Anger grew as it was revealed that Mr González has been granted a visa by France that will allow him travel across Europe - apart from close US ally Britain.

British authorities said he had been blocked under rules allowing them to ban people who have spent four or more years in prison.

Foreign Office ministers maintained their stubborn stance despite personal approaches and letters from at least a dozen MPs.

Labour MP Grahame Morris condemned the "appalling" ban.

"I suspect that the US authorities have applied political pressure on the Foreign Office," said Mr Morris.

"Even at this late hour, I appeal to the Foreign Office to show a sense of fairness and justice, and issue the visa."

Mr González was allowed to return home last year following more than 13 years in jail for exposing terrorism plans against his country hatched by rabidly anti-socialist Cuban exiles.

He is the only one of the "Miami Five" political prisoners to have been released.

The others - Gerardo Hernández, Ramón Labañino, Antonio Guerrero and Fernando González - are still languishing in US jails on terms ranging up to life for their anti-terror activities.

And legal experts and human rights organisations including Amnesty International have condemned the convictions by courts in the anti-Cuban government hotbed of Miami.

The Cuba Solidarity Campaign (CSC) vowed to mount a legal challenge against the travel ban.

Director Rob Miller confirmed that, if a statutory appeal failed, lawyers would seek a judicial review to overturn the decision.

But either would come too late for the two-day Commission of Inquiry into the Case of the Miami Five that begins this Friday.

Mr González had been slated to appear as a key witness in the case being heard by a panel of internationally renowned commissioners drawn from legal, human rights, political and academic backgrounds.

The Voices for the Five campaign behind the commission - potentially hugely embarrassing for self-styled global champion of human rights the US - is backed by a host of trade unions and big names including former archbishop of Canterbury Rowan Williams.

Mr Miller branded the last-minute ban a political act.

"The British government has the opportunity to show discretion on visa applications in circumstances like this but has chosen not to," he said.

"In the context of the already highly politicised case of the Miami Five, such a decision can only be interpreted as a political one."

And former Unite general secretary and leading Miami Five campaigner Tony Woodley said the news was "deeply unsettling."

He said: "I can't see the public interest in refusing René entry into the UK.

"On the contrary it is in the public interest to lay bare the circumstances surrounding the arrest and imprisonment of the Miami Five.

"For the sake of open-
ness and transparency we hope the UK government thinks again."