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More than half a million people have returned to Ukraine since the start of Russia's invasion in February, Ukraine's interior ministry said.
“During the past week, 144,000 people left Ukraine and 88,000 arrived. In total … around 537,000 of our compatriots have returned to Ukraine,” the ministry said, citing data from the national border service.
The returns have been facilitated by the recent reduction in intensity in fighting with concern for family and lack of security in places of refuge the main reasons.
Not all refugees are returning permanently, however, with some going back to rescue family before fleeing the war-torn country once more.
Kyiv Mayor Vitali Klitschko on Monday advised those thinking of heading back to the capital to wait a few more days.
"Firstly, there is currently a round-the-clock curfew in Kyiv region. Secondly, in certain ... towns near Kyiv, its likely that Russian occupiers left landmines, and there are (likely) a lot of unexploded munitions," he said.
Tens of thousands have been leaving Ukraine daily since the start of the war in what has become Europe's worst refugee crisis since the Second World War.
In total, more than 10 million people have left Ukraine or been internally displaced.
Of this number, more than 4.2 million Ukrainians have left the country, according to the latest UN data.
The UN's International Organisation for Migration said about 205,000 non-Ukrainians have also departed.
"The humanitarian needs are growing by the minute as more people flee the war in Ukraine," it said.
Many people who go to Ukraine's immediate western neighbours travel on to other states in Europe's Schengen open-borders zone.
But Poland's deputy interior minister said 1.5 million have remained in the country, of whom 600,000 have already obtained a Polish national identification number, used for accessing services.
Alexander Mundt, UNHCR's senior emergency coordinator in Poland, said that as people crossed the border at Medyka, he wanted to make sure they had information as to what they could expect and how they could keep safe.
"All assistance is free, and here on this side of the border the response by the Polish civil society and volunteers in every town has been staggering. I've never seen anything like it," he said.
A total of 643,058 Ukrainians have entered the EU member state, including a large number who crossed over from Moldova, wedged between Romania and Ukraine.
The vast majority are thought to have gone on to other countries.
Meanwhile, nearly 6.48 million people were estimated to be internally displaced within Ukraine as of mid-March, according to the IOM.
Before the war, 37 million people lived in territories controlled by Kyiv. That figure does not include the Crimean peninsula annexed by Russia in 2014 or two eastern regions controlled by pro-Moscow separatists.