Two of Britain’s biggest digital payments companies will merge and join the FTSE 250 index in an £800m deal designed to give them the heft to compete with the likes of PayPal. The reverse takeover will combine AIM-listed Optimal Payments with private equity-owned rival, Skrill. The enlarged company plans to join the main market as soon as the deal is completed. Optimal said it would fund the takeover with a fully underwritten £451m rights issue and more than £300m in net new debt. Lazard advised on the deal.