Panel chairman, East Timor's ex-president Jose Ramos-Horta, delivered the report's findings to UN Secretary General Ban Ki-Moon, saying recent news of sexual misconduct robbed the UN of its key asset - its integrity.

This follows disclosure that top UN officials did not promptly follow up after staff discovered alleged abuse by French soldiers in the Central African Republic.

A draft UN document obtained by the news agency AFP last week contained 480 allegations of sexual abuse from 2008 until 2013, with a third involving children and teenagers under 18.

It outlined cases in the Democratic Republic of Congo, Liberia, Haiti, Sudan and South Sudan and said peacekeepers had bought sex with anything from jewelry to television sets.

Overcome 'dark chapter', says Ramos-Horta

'Dark chapter'

Horta , a Nobel Peace Prize Laureate, said it would take "enormous effort to overcome this dark chapter."

His panel's report recommends that nations who contribute offending troops be excluded from UN missions paid from the world body's peacekeeping budget of $8 billion (7.1 billion euros).

Disciplinary action must be taken by contributing nations to ensure that immunity given while deployed still resulted in prosecution back at home, the panel said.

"Immunity must not mean impunity," it said.

Non-immune civilian UN personnel facing credible sexual abuse allegations should cooperate immediately with the host country, the panel added.

Female UN staff and human rights experts should be more involved and report regularly on the human rights situation in each area of deployment.

Investigations should be set a six-month deadline compared to the average 16 months.

Adequate resources

Those abused should be assisted by "an effective and adequately resourced" victim assistance program, the panel recommends, adding that the UN needed a new deputy secretary-general responsible for peace and security.

More generally, the Ramos-Horta report said the boom in UN peacekeeping to 130,000 troops deployed on 16 missions in world's crises regions required adaptation to meet new realities.

The report objects to calls that the UN involve itself in counter-terrorism operations, saying instead there should be a strong UN push on conflict prevention combined with "modest UN rapid deployment."

ipj/ng (AFP, AP)