Quatari-backed investment company Delta Two has offered to increase the proportion of equity in its £10.6bn bid for the supermarket giant, after weeks of negotiation threatened to end in stalemate.

More meetings are scheduled between the two parties this week, and insiders told the FT that Sainsbury's could allow its books to be opened and due diligence to begin by the end of next week.

They exact amount of increased equity has not yet been determined but it is understood to be in the region of £500m.