"Terrorist attacks" planned for the eve and during Euro 2016 have been foiled, according to the head of Ukraine's State Security Service (SBU).

The SBU said a Frenchman, who allegedly planned 15 attacks on Muslim and Jewish places of worship, in addition to administrative buildings in France, was detained in late May on the Ukrainian-Polish border.

SBU chief Vasily Gritsak said the man had made contact with illegal armed groups in the country and was interested in buying arms and explosives.

The news comes as France remains on high alert following recent attacks in Paris and Brussels.

Emergency services have been carrying out mock drills in preparation for an attack during the Euro 2016.

Last week US Department of State warned its fans that terrorists may target the European football championships.