Ukrainian women and children make up 90 percent of the refugees fleeing the war-torn country.
More than 6 million refugees have fled Ukraine since Russia began its invasion of Ukraine on February 24, according to the United Nations refugee agency.
A total of 6,029,705 people had fled Ukraine as of May 11, the United Nations showed on Thursday.
According to the UN agency’s dedicated website, many refugees travel to neighbouring Ukraine before continuing their journey, with Poland hosting the largest number of Ukrainians.
Women and children make up 90 per cent of the refugees, as Ukrainian men between the ages of 18 and 60 cannot leave the country because they are eligible for military service.
The number of refugees crossing the Ukrainian border every day has dropped significantly since the war began.
In March alone, nearly 3.4 million Ukrainians fled their country. That number fell to about 1.5 million in April.
Nearly 493,000 Ukrainians have taken refuge abroad since early May, and the United Nations estimates more than 8 million will flee Ukraine this year.
Another 8 million people are internally displaced, according to a study by the International Organization for Migration.
Ukraine was forced to spend $8.3 billion on the war with Russia, Ukrainian Finance Minister Serchy Marchenko told Reuters on Thursday.
The minister said the spending was used for everything from buying and repairing weapons to emergency support for the internally displaced.
According to the Ministry of Social Policy of Ukraine, 2.7 million people are officially registered as internally displaced persons, although the actual number is thought to be many times higher.
Marchenko said Kyiv urgently needed increased foreign support as it was forced to spend billions of dollars in additional funds for emergency wartime spending.
Ukraine’s pre-war population was 37 million, excluding the annexed Crimea peninsula and two separatist regions in the east controlled by pro-Russian separatists.