Anthropic's Claude large language model is powering the majority of complex tasks for Amazon's new Alexa+, sources tell CNBC.

About 18 months after the company first previewed the “next-gen Alexa” built with generative AI, it unveiled Alexa+, and early access will be available starting in March. Alexa+ will exist alongside the older Alexa and will cost $20 a month,

Alexa Plus will start rolling out next month in early access. It's an opt-in service and won't be available to everyone through an over-the-air update in March.