Ambassador of Ukraine to the United Kingdom of Great Britain and Northern Ireland Natalia Galibarenko has posted an open letter, asking London to tackle Kremlin-backed propagandist, British national Graham Phillips after his attempt to verbally attack and abuse a Ukrainian handicapped hostage amid a swap operation with self-proclaimed republics in Donbas."I would like to draw the attention of the British side to the situation with continuous provocative and disgraceful behaviour of the UK citizen Mr. Graham William Phillips, who currently resides in the occupied by the Russian Federation territories of Ukraine," she wrote in an open letter on September 22.