The Qatar Investment Authority has upped its stake in Sainsbury’s to 26 per cent.

The investor, which last year attempted to buy the grocer for 600p a share, has bought 12,358,000 shares in three tranches culminating on Wednesday.

Speculation that a new attempt to acquire Sainsbury’s could be on the cards may now be rekindled. The Qataris are free to bid again, after the expiry of the lock-out period that followed the collapse of last year’s takeover attempt.