London arrests a Russian diplomat on suspicion of spying . `` It is regretful that the actions of the British side were undertaken at a moment when our relations with Britain have just started to improve . London expels a British embassy staffer in response . London says the Russian embassy staff was working ` ` against UK . ''
London arrests a Russian diplomat on suspicion of spying . London expels a British embassy staffer in response . London says the Russian embassy staff was working ` ` against UK . ''