The Ukrainian government on Sunday acknowledged the allegations of discrimination against foreign citizens wishing to flee the country amid Russia's ongoing military operation.

In the wake of the operation that stared on February 24, expressions of outrage flooded social media after amateur footage and pictures showed instances where some foreign nationals were allegedly denied entry into evacuation buses and trains, while others were blocked at border points by security personnel.

The allegations prompted responses from various governments and international bodies.

The African Union said on Tuesday it was "particularly disturbed by reports that African citizens on the Ukrainian side of the border are being refused the right to cross the border to safety."

South Africa's Minister of International Relations and Cooperation Naledi Pandor said she was shocked at reports that Africans "were being pushed to the back of the line because they are black.”

In a statement on Sunday, Ukraine's Ministry of Foreign Affairs said the country does not condone discrimination of any kind.

"The Ukrainian government takes very seriously all accounts alleging unequal treatment, including when it comes to the crossing of the state border by foreign citizens," the statement read in part.

"We continue to prioritize supporting foreign citizens to leave Ukraine as safely and as quickly as possible," it added.

According to the United Nations, more than 1.5 million people have fled Ukraine since Russia launched its military operation.

Many others, mostly foreign students, are however still stranded in parts of the country amid a lack of transport means and insecurity along the travel routes.

Ukraine's Ministry of Foreign Affairs urged those who are crossing the border to comply with law and order and to have relevant documents.