The artificial intelligence startup Anthropic said on Friday it had raised an additional $4bn investment from its longtime backer Amazon.com, bringing the e-commerce giant’s total investment to $8bn, underscoring big tech’s growing generative AI investments.

Amazon will maintain its position as a minority investor, the company said. Its AWS unit will also be Anthropic’s official cloud provider.

Anthropic also said it was working with AWS’s Annapurna Labs on the development of future generations of Amazon’s Trainium chips and plans to train its foundational models on the hardware.

Britain’s competition regulator had said in September that Amazon’s partnership with Anthropic will not be referred for a deeper inquiry as it did not fall under its jurisdiction.

Anthropic, which was co-founded by former OpenAI executives and siblings Dario and Daniela Amodei, said last year it had also secured a $500m investment from Alphabet, which promised to invest another $1.5bn over time.