Sainsbury's has reportedly asked Delta Two to raise its 600p a share offer for the company.

The retailer is thought to have told Paul Taylor, who manages Delta Two, that the proposed deal is still extremely difficult to deliver with the continued opposition of the Sainsbury's family, according to reports in the Financial Times.

Meanwhile, senior figures at Sainsbury's have raised concerns that Delta Two is based on the Isle of Man, which is exempt from taxes, according to reports in the Daily Mail.