UNITED NATIONS (AP) — Secretary-General Antonio Guterres urged the world to unite and end the war in Ukraine on Thursday, calling it senseless, ruthless and “limitless in its potential for global harm.” The top U.N. human rights official said even a one-day cease-fire would prevent dozens of civilian deaths and injuries and allow several thousand others to flee Russian attacks.

The U.N. Security Council meeting on the protection of civilians and civilian infrastructure in Ukraine heard a briefing from Guterres on his recent meetings with the Russian and Ukrainian presidents that led to the first two evacuations this week from the besieged southeastern city of Mariupol and its last Ukrainian stronghold, the Azovstal steel plant. Humanitarian chief Martin Griffiths said a third convoy left for Mariupol Thursday, expects to arrive Friday morning, and hopes to evacuate civilians from the plant.

Guterres said he did not “mince words” with Russian President Vladimir Putin that his country’s Feb. 24 invasion of Ukraine is a violation of the country’s territorial integrity and the U.N. Charter and “it must end for the sake of the people of Ukraine, Russia and the entire world.”

In his meetings with Putin and Ukrainian President Volodymyr Zelenskyy, Guterres said he also focused on the need for quick action to ensure a steady flow of food and energy in open markets.

He stressed that “a meaningful solution to global food insecurity requires reintegrating Ukraine’s agricultural production and the food and fertilizer production of Russia and Belarus into world markets, despite the war.” Russia and Ukraine together produce 30% of the world’s wheat supply, 20% of its corn, and 75% of its sunflower seed oil.

High Commissioner for Human Rights Michelle Bachelet said serious violations of human rights and humanitarian law keep increasing every day. Since Russia invaded Ukraine on Feb. 24, she said, 6,731 civilian deaths and injuries have been recorded and “the real figures are considerably higher.”

From late February for about five weeks, she said, Russian forces in areas around Kyiv targeted civilian men whom they considered suspicious, detaining, beating, summarily executing them and in some cases taking them to Belarus and Russia. In other Russian-controlled areas including the Kharkiv, Donetsk, Luhansk, Zaporizhzhia and Kherson regions, she said her office continues to document arbitrary detentions and possible enforced disappearances of local officials, journalists, civil society activists, retired members of the armed forces and other civilians by Russian troops and affiliated armed groups.

“As of May 4, my office has documented 180 such cases, of which five victims were eventually found dead,” Bachelet said, adding that her staff has also heard about cases of women raped by Russian armed forces in areas under their control, and other allegations of sexual violence by both Russians and Ukrainians.

A one-day cease-fire would spare the lives of at least 50 civilians, prevent 30-70 civilians from being injured and a dozen from becoming disabled, and allow several thousand civilians “to safely leave areas where they are currently trapped in hostilities.”

“Most importantly, a cease-fire will show that the horror in Ukraine can be stopped,” Bachelet said.

Griffiths, the U.N. human rights chief, said “the reverberations of this war are being felt worldwide,” and the U.N. which has reached more than 4.1 million people with some form of aid across the country will try to get food and medical supplies to more Ukrainians.

The U.N. will also keep pushing for more civilians to leave Mariupol and the Azovstal plant, and explore “all options to reach more people in places where needs are the greatest, in other parts of Ukraine where civilians are so deeply impacted by fighting,” he said.

Russia’s U.N. Amassador Vassily Nebenzia responded accusing the West of waging a world war at the economic level and flooding Ukraine with weapons, saying the speed with which this happened “leaves us with no doubt that you’ve been preparing this for a long time.”

“Russophobia has become the main domestic national product for the Ukrainian authorities and Ukraine’s main export,” he said.

Nebenzia said humanitarian corridors for evacuating civilians from the Azovstal steel plant have been open, and were open on Thursday. He accused Ukrainian fighters in the plant of using civilians as human shields and demanding that they be provided with one ton of food and medicine “for every group of 15 liberated hostages.”

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