Ukraine has no official information on the detention in Russia of its 25 citizens on suspicion of preparing subversive activities, Ukraine's First Deputy Prime Minister Vitaliy Yarema said.

"I think this is another fake… We have no official information on this matter," Yarema told reporters in Kyiv on Friday, adding that Right Sector has denied the information on the detention of its activists in Russia.

NTV television reported on April 3, citing information obtained from the special services, that 25 citizens of Ukraine, including three Right Sector activists, had been detained on suspicion of preparing subversive activities in Russia. NTV also aired a video of the detained Ukrainians.

According to information possessed by the special services, terrorist attacks were expected to take place in several Russian regions (Rostov, Volgograd, Oryol, and Belgorod regions, and the Republics of Kalmykia and Tatarstan) on March 14 - 16, the report says.

The 25 detainees, among whom are three Right Sector activists, have confirmed that they received instructions from Ukrainian security service officials, the Russians claimed.

Their tasks included photographing the location and transfer of military equipment and the Russian Armed Forces in the areas close to the border and establishing contacts with Russian radicals.

The Ukrainian Foreign Ministry told Interfax it is probing the information received from Russia, while the Ukrainian security service described it as nonsense. The Right Sector said that this information is propaganda against their party and independent Ukraine.