A day after Russian President Vladimir Putin claimed his troops were victorious in the battle for Mariupol, a Russian military official laid out wider aims in the country’s new phase of the war in eastern Ukraine, saying Russia was seeking full control of the Donbas and southern Ukraine.

Rustam Minnekayev, acting commander of Russia’s Central Military District, said the control “will provide a land corridor to Crimea, as well as influence (over) the vital objects of the Ukrainian economy.”

The move also would open the way to Moldova, including its Russian-backed breakaway region of Transnistria, Minnekayev said.

The senior military leader made the comments at a defense industry event, where he acknowledged the second phase of the war started “just two days ago.”

Capturing Mariupol is seen as central to the new phase, but thousands of Ukrainian troops and civilians remain in the giant Azovstal steel mill complex. Putin ordered his troops Thursday not to storm the stronghold but to seal it off “so that not even a fly comes through.”

Ukraine’s Deputy Prime Minister Iryna Vereshchuk on Friday called for Russia to open up humanitarian corridors for civilians in the plant to evacuate.

NEW PHASE OF WAR: What a new phase of war means for Ukrainians in the east

USA TODAY ON TELEGRAM:Join our new Russia-Ukraine war channel

Latest developments:

►Satellite images showed what appeared to be mass graves near Mariupol, and the city’s mayor said Russian troops have buried as many as 9,000 civilians killed in the conflict in a nearby mass grave in order to cover up “military crimes.”

►The U.N.’s human rights office said Friday its investigators had documented at least 50 civilian deaths, including by summary execution, in the Kyiv suburb of Bucha.

►The International Atomic Energy Agency Director-General Rafael Mariano Grossi will travel to Ukraine next week to visit the Chernobyl nuclear power plant, the agency said Friday. Russian forces seized control of the site early in their invasion but have since left, with Ukrainian control of its operations in place.