A United Nations (UN) inspection of the Guantanamo Bay US military prison has been abandoned after access to detainees was denied by the American authorities, human rights experts announced in Geneva on Friday.

In a joint statement, five UN experts who had planned to carry out the visit expressed regret over the US's refusal to their demand for an "objective and fair assessment" of the Guantanamo Bay prison.

"We deeply regret that the United States government did not accept the standard terms of reference for a credible, objective and fair assessment of the situation of the detainees at the Guantanamo Bay detention facility," said the statement.

"Under the circumstances, we will not be traveling to Guantanamo Bay Naval Station, as doing so would undermine the principles" governing UN fact-finding missions," the statement added.

The United States had previously set the date for the five experts to visit Guantanamo on Dec. 6, to investigate alleged violations of human rights at the prison.

The United States insists, however, it will not agree to the UN request for free access to detainees held there, although it is open to international inspectors.

The UN Special Rapporteur on Torture, Manfred Nowak, rebuffed the US stand on Tuesday, saying UN inspectors will not visit the Guantanamo prison as scheduled unless Washington agrees to unrestricted access without conditions.

For the past three and half years Guantanamo Bay in Cuba has been used to house nearly 500 prisoners, who have been held without charge or access to lawyers. Most of the detainees were captured in the Afghanistan war of 2001 over suspected ties to the al-Qaida network or the Taliban regime.

Despite frequent criticism by human rights advocates, the United States says it has provided regular access to the International Committee of the Red Cross and has consulted with governments over cases of their nationals detained at the base. The approach was described as "sufficient" by US State Department deputy spokesman Adam Ereli at a news briefing Tuesday.

(Xinhua News Agency November 19, 2005)