Amazon has trained its sights on PayPal after announcing an extension to its payments service. The company's Payments Partner Programme will be extended to Amazon's merchant partners worldwide and will allow them to integrate Amazon Payments into their e-commerce platforms.

The Amazon Payments Partner Programme will enable merchants to offer a "Pay with Amazon" option at checkout. This will allow customers to securely login and pay for their goods using their Amazon credentials and the payment information they've stored on the site. In doing so, Amazon said online traders will be able offer a "trusted, easy and familiar" payment solution while also enabling them to tap into the company's huge customer base.

By extending its payments service, Amazon will be better positioned to take on the likes of PayPal, which currently enjoys somewhat of a monopoly in the online payments space and is used by more than half of the world's top 500 retailers. Meanwhile, the arrival of Apple Pay, Android Pay and Samsung Pay has narrowed the digital payments playing field even further.

Amazon is separately working on a selfie-based payments system to replace typical passwords.

Shopify, OpenCart and PrestaShop have already joined the programme, which is free to participate in and available by invitation in the US, Germany, UK and Japan. Members of the Amazon Payments Partner Programme are also eligible to receive account management, planning support, technical resources and training from Amazon, the company said.

Patrick Gauthier, vice president of Amazon Payments, said: "The Amazon Payments Partner Programme provides partners with the tools and resources needed to extend the trust and convenience of the Amazon experience to their merchant customers. We are working together across geographies and industries to help merchants grow and create experiences that delight customers throughout the shopping journey."