US banking giant Citigroup is believed to be poised to offer GBP1 billion for UK-based Internet bank Egg.

According to reports, the leading global bank is looking for small, bolt-on European acquisitions, and a GBP1 billion offer for Egg would concur with this plan.

Citigroup has refused to comment on the speculation, first reported by the Observer, but with a number of other leading banks from both sides of the Atlantic indicating an interest, Citigroup’s attention is likely to have been drawn to the UK financial services business.

If the speculation proves to be true, Citigroup will join a growing list of big name suitors from both sides of the Atlantic, including MBNA, Royal Bank of Scotland and HBOS.

Ironically, the potential for a bidding war comes as Egg’s majority owner Prudential’s interest in selling has cooled. Only 12 months ago the company could not find a buyer when it was actively touting the Internet bank.