Blackstone Group, the US private equity house, has indicated to Close Brothers that it might pay as much as £11 a share, or £1.6bn, for the merchant bank, potentially trumping the indicative 950p a share offer mooted by Cenkos Securities in November.

Shares in the London-listed bank closed up 10p at 984p on Wednesday amid rumours Blackstone had proposed an offer of between £10.40 and £10.60 a share and that the two sides were hammering out the final terms of a deal.