The Qatari-based investment firm hoping to takeover Sainsbury's has agreed to seek additional funding to finance an offer for the supermarket group.

In a statement today Sainsbury's revealed that Delta Two had agreed to secured additional equity of approximately £500 million in respect of its proposed acquisition of the retailer.

Confirmation that Delta Two is seeking extra funds to finance its proposed 600p-a-share offer for the company comes amid reports that the Sainsbury's family – who retain a stake in the retailer – are concerned that their prospective bid is comprised of too much debt.

The issue is particularly pertinent given the ongoing turmoil in the world's credit markets which has been prompted by problems in the US housing sector.

Sainsbury's revealed that Delta Two had entered into discussions with the Qatar Investment Authority to secure the additional funding it has agreed to find in respect of an offer for the supermarket chain.

But the retailer, which turned down a private equity bid led by CVC in the spring, stressed: "There can be no certainty that such funding will be forthcoming and, therefore, no certainty that an offer will be made."

Meanwhile the UK's takeover watchdog has ruled that Delta Two must table a formal bid for Sainsbury's by November 8th, or else end its interest in the company.

Sainsbury's announced that it had agreed to open its books to the investment firm last month, with the retailer stressing that under Delta Two's ownership its business would see "significant investment and further expansion".

If a deal is reached between Delta Two and Sainsbury's, the former deputy chief executive of rival supermarket group Asda – Tony Campbell – would become the retailer's non-executive chairman.