Some Russian citizens failed to explain the purpose of their visit to Ukraine / Photo from

About 150 foreigners, incl. 80 Russian citizens were refused entry to Ukraine on November 27 alone.

"For example, yesterday, about 150 foreigners were not allowed to enter Ukraine. Some of them are potentially illegal migrants. Also, about 80 citizens of the Russian Federation were unable to confirm the purpose of their journey when crossing the border. Some of them had invalid documents for crossing the border. Also [there were] those who illegally visited the temporarily occupied territories of Ukraine. They were not only denied entry but also were subject to travel ban," head of the State Border Service's media liaison office Andriy Demchenko said on Priamyi TV Channel.

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"The units of the State Border Service of Ukraine are on full alert. We use reserves, all our units have been enlarged and armed. We have also stepped up on-the-spot measures to prevent any incidents," he said.

Enhanced border control is in effect; foreign citizens, especially those who may have risk profiles are interviewed. If border guards see legal grounds for travel ban, foreigners and stateless persons are prohibited from entering Ukraine, he said.