GENEVA (Reuters) - Egypt is closing down domestic non-governmental organizations and putting travel bans on their staff in order to obstruct scrutiny of human rights issues, three independent U.N. human rights investigators said on Monday.

U.N. experts Michel Forst, David Kaye and Maina Kiai accused Egypt's government of clamping down on NGOs so that human rights violations such as the use of torture did not come to light.

“Egypt is failing to provide a safe and enabling environment for civil society in the country,” the three said in a statement. They specialize in human rights defense, freedom of expression and freedom of association.

The statement cited the Nadeem Centre for Rehabilitation of Victims of Violence, which was issued with a closing order on Feb. 17 for carrying out a "medical activity" for which it was not licensed. The center had published reports on torture.

"The organization resisted an attempt to forcibly close it on 5 April 2016 and may now be subject to legal proceedings," the statement said.

The experts also said staff at NGOs including the Nazra for Feminist Studies and the Cairo Institute for Human Rights Studies had been interrogated and threatened with arrest and prosecution if they did not comply.

Others face charges of "receiving foreign funds for illegal purposes" and "working without registration", punishable by fines and life imprisonment, the statement said.

Last Thursday, the head of the U.N. International Labour Organisation, Guy Ryder, sent a letter to Egyptian President Abdel Fattah al-Sisi, demanding he revoke a ban on recognition of independent trade unions.

“It is the responsibility of the government to ensure the application of the international labor conventions on freedom of association that it has freely ratified and which must be respected by all state authorities," Ryder wrote.

Sisi came to power in 2013 by ousting Mohamed Mursi, a Muslim Brotherhood member who was democratically elected after Egyptians revolted against one-man-rule and overthrew Hosni Mubarak after 30 years as president in February 2011.

Rights groups have long accused the government of mistreatment, something it has repeatedly denied. The government has said reports of violations are politicized and lacking in objectivity.

Human rights groups have blamed Egyptian security forces for torturing Italian student Giulio Regeni, an allegation Cairo has repeatedly denied. His body was discovered on Feb. 3, and Italian officials have ridiculed Egypt's attempts to explain his death.

(Reporting by Tom Miles)