Supermarket giant Tesco has slumped to a £6.38 billion annual loss after taking a massive writedown on the value of its property portfolio.

The bottom-line loss for the 12 months to February 28 caps a disastrous year for the chain following an accounting scandal and a series of profit warnings amid a ferocious price war with rivals.

Underlying profits were 68 per cent lower at £961 million in the period but new chief executive Dave Lewis said the company had drawn a line under the past and was seeing some encouraging signs.