John Ralfe, the former head of corporate finance at Alliance Boots and now an independent pension consultant, has said the private equity group bidding for the company should be prepared to stump up at least £500m (€735m) for Boots' pension schemes.

The independent directors of Alliance Boots have recommended an £11.1bn bid from US buyout group Kohlberg Kravis Roberts and Stefano Pessina, Boots' deputy chairman and largest shareholder.