Delta Two, the Qatari-backed fund attempting to buy Sainsbury’s, is under pressure to put more equity into the £10.6bn.

Sources close to the deal said yesterday that the credit crunch had made the deal harder to pull off.

A person familiar with Delta Two said funding from ABN Amro, Credit Suisse and Dresdner Kleinwort remained in place and that discussions with the banks were continuing.

The Sainsbury’s board has asked Delta to improve the offer by reducing the level of debt, offering more assurances over the long-term arrangement for the supermarket’s property portfolio and coming up with proposals acceptable to the pension trustees.