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Talk about starting off on the wrong foot. British Prime Minister Gordon Brown and new Russian President Dimitry Medvedev met for the first time today at the G-8 Summit in Japan, on the heels of a report that British security forces consider Russia the third most serious threat facing the country.

According to The Times of London, only al Qaeda's terrorist threat and Iran's nuclear program are seen to be more dangerous:

The services are understood to fear that Russia's three main intelligence agencies have flooded the country with agents, The Times understands. There is reported to be deep irritation within the services that vital resources are having to be diverted to deal with industrial and military espionage by the Russians

Relations between the two countries have deteriorated since the 2006 poisoning of Russian dissident Alexander Litvinenko in London, allegedly at the hands of an ex-KGB agent whom Russia refuses to extradite. The issue apparently caused a row between Tony Blair and Vladimir Putin at last year's G-8 summit, and was a topic of disucussion at today's talks.

No word so far as to whether Brown and Medvedev have hit it off better than their predecessors, only that there were some "sharp exchanges" between the two.