WeChat Pay, the mobile payment platform under internet giant Tencent, will launch in October a cross-border payment service for its Hong Kong users traveling on the Chinese mainland.

With the new service, Hong Kong WeChat users on the mainland will be able to pay for high-speed railway tickets, book taxis and buy food using the app's payment service, according to a press release from Tencent.

Users will be able to pay for services using their WeChat e-wallets and Hong Kong accounts that can be linked to the app's payment function, the company said.

WeChat Pay will automatically convert Hong Kong dollars into RMB yuan for Hong Kong users, it said.

The first group of merchants whose services will be available on the new cross-border payment service will include ride-hailing platform DiDi, group-buying service provider Meituan and restaurant reviewing app Dianping.