Nationwide Mutual, the US insurer selling Gartmore, has pulled the fund manager's US arm from the deal and will now offer only the UK business, with a price tag of at least £600m (€870m). The insurer had previously put the entire business up for sale for £1bn.

A corporate financier with access to the information memorandum on Gartmore, which was distributed just before Christmas, said: "Nationwide Mutual said it wants to focus on the US business. It does not intend to sell it."