Citibank International is looking beyond its incumbent, Fallon, and has approached three rival agencies to pitch for a pan-European brief.
Estimated to be worth around £8 million, the brief is to launch a new business-to-consumer investment product called Equity First.
The brief has originated from the company's Equity Structured Products group, which is part of Citibank's Investment division.
Unlike most of the bank's other products, which are aimed at corporate and institutional investors, Equity First is targeted at consumers, which it technically refers to as retail investors.
Fallon is not involved in the process but Citibank said the pitch would not affect the agency's hold on the main business. The network won the $150 million US account in 2000 and went on to win the £10 million UK business a year later.
In May this year, the bank also shifted its Asia-Pacific account out of Young & Rubicam and into a global Publicis/Fallon arrangement.
The latter has been tasked with producing creative work while the former handles global networking duties.
The company is also currently holding a direct marketing pitch for its credit-card business in the US. Euro RSCG DRTV in Chicago and three New York agencies - Draft FCB, Grey Direct and Young & Rubicam Brands - are involved in the pitch.
The work is currently split between 20 shops, with Wunderman handling the bulk of the business.
Fallon London's last work for the brand appeared in 2003 and featured a break-dancing dog to promote the bank's tagline "live richly".