Based on Mastercard's current valuation, Visa could be worth $9bn

It said the move would help fund its expansion, boost efficiency and pay the legal costs it faced in some markets.

Since debuting on the New York Stock Exchange in May, Mastercard's shares have risen by nearly 84%.

Visa employs 6,000 people around the world and is funded by the 21,000 firms that issue its cards and products.

Legal action

Under a restructuring plan, Visa's operations outside Europe will merge and form a new company which plans to list its shares within the next 12 to 18 months.

Visa Europe will remain as a membership association, owned and run by its 4,500 European member banks, and will become a licensee of the new Visa company.

Both Visa and Mastercard are facing legal action in the US from card issuers American Express and Morgan Stanley's Discover Card unit, accusing them of anti-competitive practices.

They also face an investigation from the UK Office of Fair Trading into the transaction fees their issuing banks charge retailers for processing payments.