Saunders has £800m to start buyout talks with WestLB

Robin Saunders has secured up to £800m from City institutions for a bid for WestLB's principal finance unit, which she has run for five years.

The high-flying American banker is expected to make a formal approach to the German bank within a fortnight - after WestLB has received a valuation of the unit from its advisers Goldman Sachs and Citigroup.

While Ms Saunders is still employed by the bank, relations between her and chief executive Jürgen Sengera have deteriorated after a deal to finance the TV rentals business Boxclever went sour.

German regulator BaFin is on Wednesday due to complete its investigation into WestLB's £350m writedown on the Boxclever deal. Instead of blaming individuals, the regulator is expected to criticise internal procedures at the bank for not keeping tabs on Ms Saunders' unit.

There has been persistent speculation that Ms Saunders would quit the bank this week. But a WestLB insider said: "I have not heard her talking about leaving imminently."

Mr Sengera is thought to want to sell the unit, which helped to rescue Bernie Ecclestone's Formula One bond, finance the redevelopment of Wembley Stadium and buy the Odeon cinema chain. Many managers of WestLB, which is majority-owned by the state of North Rhine-Westphalia, believe the bank should not be involved in such high-risk investments.

Ms Saunders refused to comment. But a friend of the banker said: "Her ideal scenario would be to buy the business from WestLB."

There has been speculation that Ms Saunders would call on some of her rich business associates, such as Mr Ecclestone, retailer Philip Green and property tycoon Robert Tchenguiz, to help buy out WestLB's principal finance unit. But a well-placed source said she had received financial backing from "blue-chip financial institutions", adding: "These are more than just informal commitments - it is formal support."

While Goldman Sachs and Citigroup have yet to publish their valuation, the principal finance unit's combined debt and equity is thought to be around £3bn.