WASHINGTON — The new U.S. ambassador to the United Nations, Nikki Haley, on Thursday blamed Russia for renewed, deadly fighting in Ukraine and said U.S. sanctions against Moscow would remain in place.

Ms. Haley’s comments at her first formal appearance at the U.N. Security Council were viewed as striking because, as a candidate, President Donald Trump had suggested he would be willing to ease sanctions on Russia.

During the campaign, Mr. Trump did not criticize President Vladimir Putin for Russia’s annexation of Crimea in 2014 or its support for armed insurgents in eastern Ukraine.

Mr. Trump suggested at one point he might be willing to recognize Crimea as part of Russia and hinted he would consider lifting sanctions that Washington and its European allies had imposed on Moscow in response.

Mr. Trump’s position on Ukraine has alarmed Europe, which fears an increasingly aggressive Russia, and was disputed by some of his Cabinet picks during their Senate confirmation hearings.

Among them was Ms. Haley, a former governor of South Carolina who is considered a rising star in the GOP.

“We do want to better our relations with Russia,” Ms. Haley said Thursday at the U.N. “However, the dire situation in eastern Ukraine is one that demands clear and strong condemnation of Russian actions.”

She cited suffering by the people of Ukraine after “nearly three years of Russian occupation and intervention.”

Sanctions will remain in place “until Russia and the separatists it supports respect Ukraine’s sovereignty and territorial integrity,” she added.Renewed fighting in eastern Ukraine has killed dozens of people, including civilians, and spawned a humanitarian crisis as electricity, water and food have become scarce in some areas in the dead of winter.

The White House has not commented on the fighting in Ukraine.

A State Department statement earlier this week condemned a “dramatic” surge in violence in eastern Ukraine, citing violations of a cease-fire with heavy artillery. But it did not mention Russia.

The New York Times and The Associated Press contributed.