LVIV, Ukraine (NewsNation) — Safe corridors intended to let civilians escape the Russian onslaught in Ukraine finally opened Tuesday. Buses packed with people began a procession along a snowy road of one city.

This comes as the number of refugees fleeing Ukraine reached 2 million on Tuesday, according to the United Nations, the fastest exodus Europe has seen since World War II.

“Today the outflow of refugees from Ukraine reaches two million people. Two million,” Filippo Grandi, the UN High Commissioner for Refugees, wrote on Twitter.

Previous efforts to establish evacuation routes crumbled amid renewed attacks.

The route out of the eastern city of Sumy was one of five promised by the Russians to offer civilians a way to escape. Even as video posted by the Ukrainian state communications agency showed people with bags boarding buses, it was not clear how long the effort would last.

“The Ukrainian city of Sumy was given a green corridor, the first stage of evacuation began,” the agency tweeted. Sumy is just 30 miles from the Russian border.

The route out of the eastern city of Sumy was one of five promised by the Russians to offer civilians a way to escape the Russian onslaught.

Michelle Bachelet, the U.N. high commissioner for human rights, is pressing for all civilians trapped by fighting in Ukraine to be allowed to leave safely. She said Tuesday she is “deeply concerned about civilians trapped in active hostilities in numerous areas.”

Bachelet also told the U.N. Human Rights Council that her office has received reports of pro-Ukrainian activists being arbitrarily detained in areas of eastern Ukraine that have recently come “under the control of armed groups.” She said there have been reports of beatings of people considered pro-Russian in government-controlled areas.

Russia pledged to allow safe passage out of some of Ukraine’s largest cities toward Belarus beginning Tuesday as the war approaches its 13th day.

The Russian Defense Ministry said safe passages would be opened for civilians from the capital of Kyiv, the southern port city of Mariupol and the cities of Kharkiv and Sumy. However, some of the evacuation routes would funnel civilians toward Russia or Belarus, which are unlikely destinations for many Ukrainians fleeing Russia’s military advance.

A spokesperson for Ukrainian President Volodymyr Zelenskyy called the proposal “completely immoral.”

Ukrainian Deputy Prime Minister Irina Vereshchuk called the proposed evacuation routes “unacceptable.” Belarus is a key ally of Russian President Vladimir Putin and served as a launching ground for the invasion.

The talks come as large cities like Kyiv and Mariupol run low on basic goods and hundreds of thousands of citizens seek a safe way out.

Russia expects another round of talks with Ukraine to take place in the very near future, a negotiator said on Monday after a round of inconclusive talks in Belarus.

“The next, fourth, round will take place in Belarus in the very, very near future,” Russian negotiator Leonid Slutsky told Russian state television. “I will not name the exact date yet. It will be determined, perhaps tomorrow.”

Moscow again announced a series of demands to stop the invasion, including that Ukraine recognize Crimea as part of Russia and recognize the eastern regions controlled by Moscow-supported separatist fighters as independent. It also insisted that Ukraine change its constitution to guarantee it won’t join international bodies like NATO and the EU. Ukraine has already rejected those demands.

Putin’s forces continued to pummel cities with rockets, and fierce fighting raged in places.

Zelenskyy has asked for additional weaponry from the West, such as planes. There is an appetite from NATO countries to supply them, but some are skeptical they will help.

“The reality is that the Russians are shooting out they’re destroying the airfields that the Ukrainians would use to fly those,” cybersecurity expert Dmitiri Alperovitch said on “NewsNation Prime.” “Pretty soon, they won’t have any runways to launch them from.”

Ukraine has also asked for NATO to declare a no-fly zone around the country, which has been rejected for fears it could start World War III.

“It’s going to be very, very difficult for the Ukrainians really to conduct a sustained air campaign,” Ret. Lt. Col. James Carafano said on “NewsNation Prime.” “So I know it sounds good. But it just doesn’t really kind of pass the common sense test.”

In one of the most desperate cities, the encircled southern port of Mariupol, an estimated 200,000 people were hoping to flee, and Red Cross officials waited to hear when a corridor would be established.

The Ukrainian government has proposed eight humanitarian corridors, including from Mariupol, that would allow civilians to travel to the western regions of Ukraine where there is no Russian shelling.

Russia’s plan to quickly overrun the country has been met with fierce resistance by Ukrainians. Russian forces have also continued their offensive, opening fire on the city of Mykolaiv, 300 miles south of the capital, according to Ukraine’s General Staff.

Hundreds of thousands of civilians attempting to flee to safety over the weekend were forced to shelter from what Ukrainian officials said was Russian shelling in cities in the center, north and south.

The bodies of at least 13 civilians were recovered from the rubble after a factory in the town of Makariv in the Kyiv region was hit, local emergency services said. Five people were rescued of the 30 believed to have been there at the time.

Many residents have been trapped in cities under fire. Food, water, medicine and almost all other supplies were in short supply in the southern port city of Mariupol, which an estimated 200,000 people are trying to flee but where an earlier cease-fire collapsed. Russia and Ukraine have traded blame for the failure.

Russian troops have made significant advances in southern Ukraine and along the coast, but many of its efforts have become stalled, including a 40-mile long military convoy that has been almost held up for days north of Kyiv.

Putin has now deployed into Ukraine nearly 100 percent of the more than 150,000 forces that he had pre-staged outside the country before the invasion, a senior U.S. defense official said on Monday.

“That’s our best estimate right now,” the official said, speaking on condition of anonymity.

The death toll from the fighting, meanwhile, remains unclear. The U.N. human rights office says it has been able to confirm the deaths of 406 civilians in Ukraine since the beginning of the Russian invasion, but also warned that the number is a vast undercount.

The fighting has sent energy prices surging worldwide, stocks plummeting and is threatening the food supply and livelihoods of people around the world who rely on farmland in the Black Sea region.

On Tuesday, Britain’s defense secretary said that there are reports Ukrainian special forces destroyed more than 20 Russian helicopters on the ground overnight as Russia’s invasion of Ukraine continues to face logistical problems and fierce resistance.

Russia’s advance toward Kyiv continues to face pressure from Ukrainian forces around the nearby towns of Hostomel, Bucha, Vorzel and Irpin, the U.K. Defense Ministry said in an intelligence update released late Monday.

In addition, a lengthy Russian column remains stuck on the road north of Kyiv.

Defense Secretary Ben Wallace said Russian forces are becoming more and more desperate in the face of such military and supply holdups, leading to “indiscriminate shelling” of civilians.

“We’ve also recognized that probably the biggest single casualties, so far in the war, are Russian military soldiers who have been let down by appalling leaders, appalling leadership and appalling plans. And now you see them, literally, at large scales dying.”

Western nations have placed heavy sanctions on Moscow to isolate it from global commerce and are now considering banning Russian oil imports.

Oil prices spiked to their highest levels since 2008 amid the prospect of less supply from Russia, the world’s biggest exporter of oil and gas.

The Russian invasion has also pushed 1.7 million people to flee the country, creating what the head of the U.N. refugee agency called “the fastest-growing refugee crisis in Europe since World War II.”

As tensions reach a boiling point worldwide, NewsNation’s Leland Vittert said Putin’s continued aggression poses a threat to other democracies.

“If Ukraine can be invaded and overtaken by Vladimir Putin, so can any other democracy in Europe,” Vittert said on “Morning in America.” “Vladimir Putin sees the existence of democracies, especially in Eastern Europe, as a threat to him and a threat to his greater goal of bringing back the glory of Mother Russia and the glory of the Soviet Union.”

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