Cameron: 'Punish the Russians for their attack on Georgia by banning them from our shops'

The Conservative leader called on the Government to take a much tougher stance against Moscow, including suspending Russia from the G8, summoning the country's ambassador to make a diplomatic protest and fast-tracking Georgia's membership of Nato.

Mr Cameron, who flew to the Georgian capital Tbilisi on Saturday, said: 'Russian armies can't march into other countries while Russian shoppers carry on marching into Selfridges.'

Shop shake-up: David Cameron met Georgia's President Mikheil Saakashvili at the weekend

His comments will increase pressure on ministers widely accused of doing too little in response to the crisis.

In a speech at his monthly press conference Mr Cameron condemned Russia's actions as 'completely unacceptable', with 'worrying echoes with the darkest chapters of European history'.

He said: 'Russia has used massive and disproportionate force - countries that want international respect do not attack their neighbours.'

He added: 'It is clear that stability in the Caucasus - and Russia's behaviour there and beyond - is a matter for the security of Britain and our allies.'

LibDem foreign affairs spokesman Edward Davey accused Mr Cameron of 'posturing', and making promises over Nato membership he could not fulfil.

He said: 'It is simply not credible for Britain and Nato to make confetti commitments to protect every nation.'