Russia said Friday that it plans to take full control of Donbass and southern Ukraine as part of the second phase of its "special military operation," Russian news agencies reported. Teams of volunteers collected corpses in the port city of Mariupol after Moscow declared "victory" – apart from the Azovstal steel plant where Ukrainian forces continue to resist.

The statement from the deputy commander of Russia's central military district, Rustam Minnekayev, is one of the most detailed about Moscow's latest ambitions in Ukraine and suggests Russia does not plan to wind down its offensive anytime soon.

Minnekayev did not mention them by name, but two major Ukrainian cities in southern Ukraine, Odessa and Mykolaiv, remain under Ukrainian control.

The Interfax and Tass news agencies cited him as saying that full control of southern Ukraine would improve Russian access to Moldova's pro-Russian breakaway region of Transnistria, which borders Ukraine and which Kyiv fears could be used as a launchpad for new attacks against it.

Kyiv earlier this month said that an airfield in the region was being prepared to receive aircraft and be used by Moscow to fly in Ukraine-bound troops, allegations Moldova's defense ministry and authorities in Transnistria denied.

"Control over the south of Ukraine is another way to Transnistria, where there is also evidence that the Russian-speaking population is being oppressed," the Tass news agency quoted Minnekayev as saying at a meeting in Russia's central Sverdlovsk region.

Minnekayev was not cited as providing any evidence for or details of that alleged oppression.

He was quoted as saying that Russia planned to forge a land corridor between Crimea, the Black Sea peninsula which it annexed in 2014, and Donbass in eastern Ukraine.

The last Ukrainian fighters left in the port city of Mariupol in Donbass and are holed up at a vast industrial facility that President Vladimir Putin has ordered to be blockaded rather than stormed. Mariupol sits between areas held by Russian separatists and Crimea. Its capture would allow Russia to link the two areas.

Minnekayev was cited as saying by Russia's RIA news agency that media reports of Russian military setbacks were wide of the mark.

"The media are now talking a lot about some failures of our armed forces. But this is not the case. In the first days ... the tactics of Ukrainian units were designed to ensure that, having pulled ahead, individual groups of Russian troops fell into pre-prepared ambushes and suffered losses," RIA cited him as saying.

"But the Russian armed forces very quickly adapted to this and changed tactics."

According to RIA, he also said that daily missile and other strikes against Ukrainian forces meant Russia could do serious damage without losing troops.

Russia sent tens of thousands of troops into Ukraine on Feb. 24 in what it called an operation to degrade its southern neighbor’s military capabilities and root out people it called dangerous nationalists.

Ukrainian forces have mounted stiff resistance and the West has imposed sweeping sanctions on Russia in an effort to force it to withdraw its forces.

New offensive in eastern Ukraine

Russia pressed its new offensive in eastern Ukraine on Friday while in the port city of Mariupol, teams of volunteers collected corpses from the ruins following Russia's victory claim.

Ukraine's general staff said Russian forces had increased attacks along the whole front line in the east of the country and were trying to mount an offensive in the Kharkiv region, north of Russia's main target, Donbass.

Russia says it has won the battle of Mariupol, the biggest fight of the war, having made the decision not to try to root out thousands of Ukrainian troops still holed up in a huge steelworks that takes up much of the center of the city.

Kyiv says 100,000 civilians are still inside the city and need full evacuation. It says Moscow's decision not to storm the Azovstal steelworks is proof that Russia lacks the forces to defeat the Ukrainian defenders.

In a Russian-held section of the city, the guns had largely fallen silent and dazed-looking residents ventured out on streets to a background of charred apartment blocks and wrecked cars. Some carried suitcases and household items.

Volunteers in white hazmat suits and masks roved the ruins, collecting bodies from inside apartments and loading them on to a truck marked with the letter "Z," a symbol of Russia's invasion.

Maxar, a commercial satellite company, said images from space showed freshly dug mass graves on the city's outskirts. Ukraine estimates tens of thousands of civilians died in the city during nearly two months of Russian bombardment and siege.

The United Nations and Red Cross say the civilian toll is still unknowable but at least in the thousands. Russia denies targeting civilians and says it has rescued the city from nationalists.

In Zaporizhzhia, where 79 Mariupol residents arrived in the first convoy of buses permitted by Russia to leave for other parts of Ukraine, Valentyna Andrushenko held back tears as she recalled the ordeal under siege.

"They (Russians) were bombing us from day one. They are demolishing everything. Just erase it," she said of the city.

Kyiv said no new evacuations were planned for Friday. Moscow says it has taken 140,000 Mariupol residents to Russia; Kyiv says many of those were deported by force in what would be a war crime.

Mariupol Mayor Vadym Boychenko, who is no longer inside Mariupol, said: "We need only one thing – the full evacuation of the population. About 100,000 people remain in Mariupol."

Boychenko also accused the Russians of "hiding their military crimes" by taking the bodies of civilians from the city and burying them in Manhush.

In a late-night address, Ukraine's President Volodymyr Zelenskyy said Russia was doing all it could "to talk about at least some victories."

"They can only postpone the inevitable – the time when the invaders will have to leave our territory, including from Mariupol, a city that continues to resist Russia regardless of what the occupiers say," Zelenskyy said.

Abandoning the effort to defeat the last Ukrainian defenders in Mariupol – Donbass' main port – frees up more Russian troops for the main military effort, an assault from several directions on the towns of Kramatorsk and Sloviansk, to cut off the main Ukrainian military force in the east.

In a televised meeting at the Kremlin on Thursday, Putin congratulated his defense minister and Russian troops for the "combat effort to liberate Mariupol" and said it was unnecessary to storm the Azovstal plant.

The Kremlin leader, who has appeared only rarely in public in recent weeks, spoke hesitantly, barely above a whisper, squeezing the end of the table tightly with one hand throughout the 10-minute video clip released by the Kremlin.

British military intelligence also reported heavy fighting in the east as Russian forces tried to advance on settlements but said the Russians were suffering from losses sustained early in the war and were sending equipment back to Russia for repair.

Russia calls its invasion a "special military operation" to demilitarize and "denazify" Ukraine. Kyiv and its Western allies reject that as a false pretext for a war that has killed thousands and uprooted a quarter of Ukraine's population.

The United States authorized another $800 million in military aid for Ukraine on Thursday, including heavy artillery and newly disclosed "Ghost" drones that are destroyed after they attack their targets.

"We're in a critical window now of time where they're going to set the stage for the next phase of this war," U.S. President Joe Biden said.