Following some high-level diplomacy, Secretary of State Clinton says Cuba refuses to cooperate with the U.S. to preserve it as a scapegoat for Cuba's failures. "Cuba's response to recent US efforts to improve relations had revealed 'an intransigent, entrenched regime' in Havana, said the US secretary of state. The Cuban authorities have long blamed a 48-year US trade embargo for holding back the country's development. The US says the embargo will remain until Cuba improves human rights. Relations between Washington and the communist government in Havana have soured in recent months after early expectations of an improvement under the Obama administration. The BBC's Michael Voss in Havana says initial hopes of improved relations are receding with both sides resorting to much stronger and less diplomatic language."