Robert Tchenguiz has built up a 3% stake in Sainsbury’s, stoking speculation that he could be involved in a bid for the retailer.

The Iranian entrepreneur is thought to be considering his strategic options with adviser Citigroup, which has been helping him to acquire shares in the takeover target.

News of Tchenguiz’ increasing interest in Sainsbury’s has broken just a day after the Takeover Panel issued a ‘put up or shut-up’ deadline to the retailer’s other known suitor, the private equity consortium led by Blackstone, CVC and KKR.

Sainsbury’s first captured the attention of property entrepreneurs in January after City analysts said they thought Sainsbury’s property estate could command a value of £7.5bn on the open market - around £2.5bn more than the retailer’s estimate.

Tchenguiz is a regular predator of listed companies with valuable underlying property assets. He bought rival supermarket chain Somerfield for £1.8bn in 2005 and attempted a takeover of pub company Mitchells & Butler last year.