BRUSSELS (Reuters) - Inmates at Guantanamo Bay prison are treated better than in Belgian jails, an expert for Europe's biggest security organization said on Monday after a visit to the controversial U.S. detention center.

"At the level of the detention facilities, it is a model prison, where people are better treated than in Belgian prisons," said Grignard.

Grignard told a news conference that prisoners' right to practice their religion, food, clothes and medical care were better than in Belgian prisons.

"I know no Belgian prison where each inmate receives its Muslim kit," Grignard said.

U.N. investigators last month demanded that the U.S. government close the prison without further delay, alleging a host of violations of human rights and torture.

They did not visit the site because they were not allowed to conduct interviews with the prisoners.