LONDON -- Ant Financial, an Alibaba affiliate, announced on Thursday it has taken over UK-based international payments group WorldFirst, marking the most significant foreign fintech acquisition by the Chinese financial services company.

Ant Financial, operator of the world's leading payment platform Alipay, said in a statement that Alipay will work with WorldFirst to better serve global small businesses, promote inclusive finance and contribute to sustainable development in the world.

WorldFirst, now a wholly-owned subsidiary of Ant Financial, will continue to be headed by co-founder and CEO Jonathan Quin. The UK-headquartered company will continue its regulated business with global operations, including in the Chinese mainland and Hong Kong.

Quin wrote in a letter to its customers that the products and services of Alipay and WorldFirst are highly complementary and that WorldFirst will be able to offer even better products and services by becoming part of a larger group.

"By combining WorldFirst's award-winning currency account, international payments and currency exchange products with Ant Financial's range of financial technology solutions, we will advance our shared aims of building the best global platform for international trade and bring fast and affordable services to individuals, small and medium-sized businesses and online merchants around the world," Quin wrote.