According to the Telegraph, Barclays will request permission to go ahead with a share-based offer worth $84 billion, but with the RBS-led consortium offering $13.7 billion more, some investors are calling for the bank to pull out.
The bid is thought to have fallen short because of the collapse of Barclays' shares in the US sub-prime crisis.
But most investors want Barclays to stay in the running in case the Dutch regulator blocks the offer from RBS. Barclays will also forgo a $276 million break-fee if it pulls out.
The liquidity crisis had added to pressure on RBS, and Merrill Lynch, the consortium's adviser, is haggling over the price it wants to charge for the underwriting of two bond issues involved in the funding of the deal.
RBS and Fortis, the consortium partner, may raise funds in US preference shares, to get to the $6.8 billion needed by the close of the offer on October 5th.