Huawei, a Chinese tech giant, is adding Amazon's artificial intelligence application Alexa to its flagship smartphone for its US launch.

Huawei, the No 3 global smartphone brand, announced at last week's Consumer Electronics Show that its Mate 9 handset would include the personal digital assistant developed by Amazon.

The Mate 9, a large-screen "phablet" marketed as a rival to the big handsets from Apple and Samsung, will be available to US buyers in "early 2017", the Chinese firm said at the Las Vegas tech show.

Huawei said this is the first smartphone to pre-install Amazon Alexa, a cloud-based, voice-activated digital assistant that can control smart home devices or respond to questions.

Amazon is making Alexa available to third parties as it seeks to boost its presence in the consumer electronics field with artificial intelligence and home automation.

Alexa is battling similar services developed by Google, Microsoft and Apple that can be used on a smartphone or home speaker hub.

Huawei, whose US presence is limited mostly through direct-to-consumer sales of unlocked devices, launched the Mate 9 late last year in Europe and other markets, but without Alexa.

Buyers in those markets will be able to install the Amazon application through an over-the-air update.

The Mate 9, which could get a boost from the woes of Samsung's recalled Note 7 handset, is touted by the company as a high-performance device with fast charging and extended battery life, and upgraded photography with a dual-lens system developed in cooperation with Leica.

Huawei claims its fast computing performance will remain for at least 18 months, and that its chipset is designed with machine learning capabilities to make the phone smarter as it is used.

"Response to the Mate 9 has been extremely positive, resulting in numerous industry awards and accolades," said Zhu Zhendong, president of Huawei Device USA.

"With the Mate 9, we set out to improve every element of the smartphone experience, creating a dynamic and powerful device that takes a big step forward in what consumers expect in a smartphone. We're excited to introduce the Mate 9 flagship device to the US market."

The launch was the second in two days at the CES for Huawei. On Tuesday, it unveiled its upgraded midrange Honor 6x smartphone that will be sold starting this month in 13 markets, including the United States.