LONDON: Global payments giant Mastercard has said it will invest $300 million as a cornerstone investor in the planned London float of payments processor Network International.

Dubai-based Network International is the largest payments processor in the Middle East and Africa and set to be the first international IPO in London this year.

Network International is targeting a valuation of around $3 billion according to banking sources.

Mastercard said it would invest in shared projects with Network International in the Middle East and Africa as part of the deal.

Network International is currently jointly owned by Dubai bank Emirates NBD and private equity firms Warburg Pincus and General Atlantic.

Mastercard said its investment would be based on the same terms as institutional investors participating in the IPO.

The deal is subject to Mastercard's ownership being limited to 9.99 percent and Network International achieving a free float of at least 25 percent. ($1 = 0.7575 pounds)

(Reporting by Iain Withers Editing by Rachel Armstrong) ((Iain.Withers@thomsonreuters.com; +44(0)207 542 3330;))