The top United Nations human rights body has narrowly passed a resolution calling on Cuba to accept a visit by a human rights investigator.
Cuba's crackdown set back its slowly improving relations with the world
The 53-member Human Rights Commission passed the resolution by 24 votes to 20, with nine abstentions.
But the commission firmly rejected an amendment proposed by Costa Rica which expressed "deep concern" about recent sentences handed down to about 75 members of Cuba's political opposition and which called for them to be released.
Those jailings, along with last week's rapid trials and executions of three men convicted of a ferry hijacking, have prompted expressions of alarm from the United States, European Union and human rights groups.
This latest resolution calls on Cuba to accept a visit by French law expert Christine Chanet, whom Cuba has refused to allow in. It says such a visit could infringe its sovereignty.
Peru and Uruguay put forward the resolution and it was supported by several Latin American countries, including Mexico, a traditional Cuban ally.
That drew an angry response from the Cuban representative, Juan Antonio Fernandez, who told the meeting the resolution had been proposed by Latin American "lackeys" working for the US.
Earlier, in response to the tougher amendment proposed by Costa Rica and backed by EU countries - which was eventually rejected by 31 votes to 15 - Cuba retaliated by putting forward another proposal.
Hijackings have escalated recently
This criticised the "unilateral and illegal blockade against Cuba imposed by the United States, which constitutes a flagrant violation of the human rights of the Cuban people, in particular their right to food and health".
That motion was also rejected, by 26 votes to 17.
Cuba blames the United States for a wave of "aggressions and provocations".
There have been a string of hijackings or attempted hijackings recently by Cubans trying to reach American soil - tempted, argue the Cubans, by a virtual US guarantee that every Cuban who makes it will be granted residency.
And Havana accuses James Cason, the US representative in Cuba, of recruiting spies and inviting dissidents to provocative high-profile events at his home.
US relations plunge
On Wednesday, Mr Fernandez also accused Cuba's critics of saying nothing about the hundreds of Afghan war captives held without charge at the US naval base at Guantanamo Bay in eastern Cuba, "who have remained in legal limbo for more than a year".
It emerged on Thursday that Washington may respond to the sharp deterioration of relations by further tightening sanctions on Havana.
President George W Bush is considering halting flights to Cuba and banning Cuban exiles from sending money back - which would cost Cuba up to $1bn in annual revenues, the New York Times newspaper reported.