By Neil Mackay

HUNDREDS of Russian spies are now operating in the UK - many times more than at the height of the cold war, according to a former KGB lieutenant colonel writing today in the Sunday Herald.

Konstantin Preobrazhensky claims Russia is now in the midst of an unprecedented espionage war against British interests at home and abroad, and says it is a spying war for which Britain is wholly unprepared.

Preobrazhensky's comments follow claims earlier this week by Whitehall that the murder of former Russian agent Alexander Litvinenko was carried out with the backing of the Russian state.

Litvinenko was a fierce critic of former Russian president Vladimir Putin and died after being poisioned with radioactive polonium-201 in London in 2006.

Preobrazhensky, who was a close friend of Litvinenko, was granted political asylum by the US in 2006 after fleeing Russia following outspoken criticism of Putin and Russian intelligence operations.

He says: "Russian agents have a strangle-hold on the UK because Putin modernised the Russian concept of intelligence"