Head of the Security Service of Ukraine (SBU) Vasyl Hrytsak has not received an official response from the French side regarding the detention of a French citizen who intended to commit acts of terrorism at Euro 2016.

"Unfortunately, I don't know yet the official response of the French government. We are acting within the framework of international conventions that provide for cooperation between the special services. I can only say that work underway ... was being done in a well-balanced manner, and the detention of the suspect at the border was not a surprise for our counterparts," Hrytsak said at a briefing in Kyiv on Monday.

Speaking about the reasons why the detention of the Frenchman was reported only now, the head of the Security Service cited security concerns.

"It would have be beneficial for Ukrainian security services to make the announcement on May 21, when the French citizen was detained [planning to commit acts of terrorism at Euro 2016], but security concerns were more important for us," Hrytsak said.