A day after the United Nations reported that Afghan forces and their U.S. allies had killed more civilians in Afghanistan than the Taliban and the Islamic State had in the first quarter of 2019, a U.S. envoy to the country said Washington was “distressed” by the news.

“We deeply regret any loss of innocent life during military operations. We never target innocents,” U.S. Special Representative Zalmay Khalilzad wrote in tweets on Thursday morning. “War is treacherous & unintended consequences are devastating.”

Khalilzad, appointed by President Trump to help restart Afghan peace talks, suggested the civilian deaths underscored the need for a peace agreement with the Taliban.

“I challenge Talibs to join other Afghans and work to make this the year of peace,” he wrote, referring to supporters of the Islamist political movement and insurgency.

In its report, the U.N. Assistance Mission to Afghanistan found that Afghan and international forces had caused 305 deaths and 303 injuries among civilians, compared with 227 deaths and 736 injuries at the hands of groups such as the Taliban and the Islamic State. UNAMA has been documenting civilian casualties in Afghanistan since 2009.

According to the U.N. report. pro-government forces were responsible for 53 percent of civilian deaths in the first quarter, though insurgent groups were responsible for 54 percent of all civilian casualties, a figure that includes injuries and deaths.

Overall, civilian casualties decreased in this period, the report found, dropping 23 percent year on year to mark the lowest first-quarter number since 2013. The report noted the decline was “driven” by a lower number of suicide bombings, but it was unclear whether the harsh winter or planned peace talks in Doha, Qatar, played any role.

But the report also noted the rising toll from airstrikes and search operations by pro-government forces. Women and children made up half of the civilian casualties from aerial operations, it stated.

Tadamichi Yamamoto, the U.N. special representative for Afghanistan, said all sides need to take “urgent steps” to prevent harm to civilians. “Pro-government Forces are called upon to take immediate measures to mitigate the rising death toll and suffering caused by airstrikes and search operations,” Yamamoto said in a statement released Wednesday.

In his messages on Twitter, Khalilzad said the United States was “distressed by reports of civilian casualties, each one an unnecessary victim of a war that has gone on too long.”

A veteran diplomat who was born in Afghanistan, Khalilzad has been deeply involved in the U.S. role in the country since 2001, when he advised the administration of George W. Bush. He later became a special envoy to the country and served as U.S. ambassador to Kabul from 2003 to 2005.

Since assuming his current position in September, Khalilzad has been an advocate for Afghan peace negotiations. Along with Secretary of State Mike Pompeo, Khalilzad expressed regret after talks between the Afghan government and the Taliban, scheduled to take place in Doha this month, were indefinitely postponed.

“A bump in the road isn’t reason to slow down,” Khalilzad tweeted Monday.

A report released by the United Nations in February found a record number of civilians were killed in 2018: 3,804. The report stated that more than 32,000 noncombatants have been killed and almost 60,000 injured in the past decade in Afghanistan.

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