Delta Two's £10.6bn bid for Sainsbury's was thrown into doubt yesterday as a top-10 investor in the supermarket sold its stake.

Lansdowne Partners sold 12 million shares, a third of its holding, for about £65m, much less than the £6-per-share offered by the Qatari-backed investment fund.

Lansdowne said the move was a “simple portfolio de-risking exercise. But analysts said its decision to bail out before the outcome of the takeover bid was clear, would fuel worries that crisis in the credit markets was making Delta Two's plans to raise £7.5bn in debt to buy the chain unrealistic.

According to investment banking experts Dealogic, 67 transactions worth more than a combined £12bn have been called off in recent weeks as the debt markets reel from the turmoil in the US market for sub-prime mortgage.