Photos and videos show long waits, traffic jams at border crossings as thousands try to leave Ukraine

Nearly 400,000 Ukrainians have crossed into neighboring countries since the start of the conflict, the United Nations High Commissioner for Refugees said Sunday. More than half have gone to Poland, the refugee agency said, and people are also streaming into Moldova, Slovakia, Romania and Hungary.

Mapping the Russian invasion of Ukraine

Traffic data from Google showed severe backups at nearly every border crossing Sunday at 10:25 pm local time, particularly at crossings into Poland, where thousands of people are still waiting to leave. Ukrainians trying to leave by train and bus also struggled with crowds and service halts.

Officials warn that the flow of refugees is likely to escalate into a full-blown humanitarian crisis.

On Sunday, Ylva Johansson, the European Union’s home affairs commissioner, said member nations need to be prepared to support “millions” of Ukrainians in the coming months.

Ukrainians can stay, visa-free, for 90 days in E.U. nations, and Johansson said the E.U. will request member nations next week to grant asylum to Ukrainians coming to Europe for up to three years.

“The tidal waves of suffering this war will cause are unthinkable,” said U.S. ambassador to the United Nations Linda Thomas-Greenfield on Wednesday, saying that up to 5 million Ukrainians — roughly 10 percent of the population — could become refugees if Russia’s assault continues.

If that scale of exodus holds, this will be Europe’s worst humanitarian emergency since 2015, when more than 1 million people were displaced from Syria, Iraq and Afghanistan.

368,000 Ukrainians flee to European countries, including some that previously spurned refugees

Nearly half of those fleeing have gone into Poland, Tomasz Praga, who heads the country’s border guard, said Sunday. In total, the country is expected to receive up to one million refugees.

The backlog persisted through the weekend. On Saturday, a spokesperson for the U.N. refugee agency reported a nine-mile-long backlog at one crossing, with some people waiting 40 hours in 28-degree temperatures at night.

On Sunday, a Post reporter saw lines of cars stretching for 20 miles from the border crossing into Medyka, Poland.

In videos, photos and maps, how Russia’s invasion of Ukraine is unfolding on the ground

Slovakia declared a state of emergency Saturday morning due to the mass influx of foreigners caused by the war. The government approved an infrastructure bill of 13 billion euros to strengthen the Ukrainian border infrastructure and complete asylum facilities.

Nearly 80,000 Ukrainians have crossed into Hungary, according to border police.

Satellite images provided by Maxar shows a 4-mile-long line at the border crossing in Siret, Romania, on Friday. Romania’s border police said some 43,000 Ukrainian citizens crossed the border in the first three days of the conflict. The Romanian defense minister said earlier this week that the NATO country of 19 million could take in up to a half-million refugees.

Moldova’s President Maia Sandu said Sunday that nearly 70,000 Ukrainian citizens had entered the country in the past four days. Moldova’s border police said the largest flows were coming from the Tudora and Palanca crossings.

How Americans can donate to help people in Ukraine

As conflict intensified, Ukraine’s border guards were ordered Friday to stop all male citizens between the ages of 18 and 60 from leaving the country, disappointing many that got to border checkpoints after hours of travel and wait.

“If I could go, too, I would,” Vitali, 31, told The Post after his wife and child crossed into Poland, with tears in his eyes. “It’s brutal.”

Leslie Shapiro and Monica Ulmanu contributed to this report.