The British government summoned the Russian ambassador and sanctioned two people for what it said was a sustained but failed attempt by Russian cyber spies to interfere in British politics.

Britain's foreign ministry said a hacking group dubbed "Cold River" by cybersecurity researchers, working on behalf of Russia's Federal Security Service (FSB), had targeted British politicians, journalists, and non-profit groups over a period of several years.

Moscow routinely casts cyberespionage accusations as false smears by the West and its foreign ministry has previously dismissed Reuters reporting on Cold River as anti-Russian propaganda.

(Reporting by Reuters; Editing by Kevin Liffey)