Saudi-led coalition appear to be responsible for a "disproportionate amount" of attacks on civilian areas in Yemen

(Adds comment by the U.S. ambassador and New Zealand ambassador)

By Michelle Nichols

UNITED NATIONS, Dec 22 (Reuters) - The United Nations High Commissioner for Human Rights told the U.N. Security Council on Tuesday that a Saudi-led coalition's military campaign in Yemen appeared to be responsible for a "disproportionate amount" of attacks on civilian areas.

Speaking at the council's first public meeting on Yemen since the Saudi-led bombing campaign began nine months ago, Zeid Ra'ad al Hussein said he had "observed with extreme concern" heavy shelling from the ground and air in civilian areas of Yemen including the destruction of hospitals and schools.

He said all parties to the conflict were responsible, "although a disproportionate amount appeared to be the result of air strikes carried out by coalition forces."

A Saudi-led Arab coalition intervened in Yemen's civil war in March to try to restore the government after it was toppled by Iran-allied Houthi forces, but a mounting civilian death toll and dire humanitarian situation has alarmed human rights groups.

Western nations have been quietly increasing pressure on Saudi Arabia to seek a political deal to end the conflict, U.N. diplomats have said. Diplomats said Tuesday's session was convened to shine a spotlight on the conflict and pressure all sides to seek a negotiated end to the bloodshed.

U.S. Ambassador to the United Nations, Samantha Power, president of the council for December, said all parties must abide by humanitarian law. She said the Houthis must stop indiscriminate shelling of civilians and cross-border attacks.

"We will also continue to urge the Saudi-led coalition to ensure lawful and discriminate targeting and to thoroughly investigate all credible allegations of civilian casualties and make adjustments as needed to avoid such incidents," Power said.

Warring parties in Yemen agreed to a renewable seven-day ceasefire under U.N. auspices that started Dec. 15, but it has been repeatedly violated.

"I further call on the council to do everything within its power to help restrain the use of force by all parties and to urge all sides to abide by the basic principles of international humanitarian law," Zeid said.

The United Nations says the conflict has killed nearly 6,000 people, almost half of them civilians. Zeid said more than 600 children had been killed and some 900 injured - a five-fold increase compared to 2014.

A first round of peace talks adjourned on Sunday and the U.N.'s envoy to Yemen, Ismail Ould Cheikh Ahmed, said the two sides would meet again on Jan. 14.

Ahmed told the council there were still deep divisions and "trust between the parties remains weak."

The United Nations has designated Yemen as one of its highest-level humanitarian crises, alongside emergencies in South Sudan, Syria and Iraq. It says more than 21 million people in Yemen need help, or about 80 percent of the population.

"The potential ramifications of a failed state in Yemen would almost inevitably create safe havens for radical and confessional groups such as the so-called (Islamic State)," Zeid told the 15-member council.

Rights groups have criticized the United States, Britain and other Western countries for supplying arms to the Saudis that have been used in the war, and they have also accused the Arab forces of using cluster bombs, which are banned by most states.

"Hostilities in and around civilian areas, including the use of heavy weapons and cluster munitions, as well as air strikes and anti-aircraft fire, have inflicted an unacceptably high toll on the civilian population," New Zealand U.N. Ambassador Gerard van Bohemen told the council.

The Saudi U.N. mission was not immediately available for comment on Zeid's remarks and accusations about the use of cluster bombs. (Additional reporting by Louis Charbonneau; Editing by Louis Charbonneau and Paul Simao)

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