Mastercard is looking at ways to integrate its payments system into voice assistants made by Google and Amazon to let people pay by talking to a device, a top executive from the company told CNBC on Monday.

The U.S. payments giant has a product called Masterpass that allows a user to upload credit card details and acts as an easy way to pay for things online.

Recently, the company launched a facility for people to pay with Masterpass for products within Facebook Messenger. A user would interact with a brand by messaging them on Messenger. When they buy a product, Masterpass can be used to pay.

It's a trend Mastercard is calling "conversational commerce" and it extends to voice too. Ann Cairns, vice chairman at Mastercard, said that buying items using voice assistants like Amazon's Alexa or Google Assistant will "become very big" in the future.

When asked whether Mastercard is looking to integrate Masterpass with these voice assistants, Cairns said, "Yes, of course."

"We're looking at all of these technologies and we're thinking about how they link on the Mastercard network," Cairns told CNBC at the Money 20/20 Europe fintech conference in Amsterdam, Netherlands, on Monday.

Masterpass can be used to pay for apps on the Google Play store. Mastercards can be used on Amazon and Google already too. Cairns said any integration into voice assistants would be an extension of the relationship between Mastercard and the technology firms.

"We're already integrated into many of Amazon's and Google's products so really it's more of a new product function, product line, that we're looking at. But we're also looking at how is artificial intelligence deployed," she said.

Mastercard is watching for ways to adapt to the shifts in consumer behavior when it comes to payments. Masterpass was the company's answer to products such as Apple Pay. A number of technology firms are increasingly dipping their toes into financial services and Mastercard is trying to stay ahead through some of these technology products.