The cloud businesses of Amazon and Microsoft could face stricter scrutiny from European Union regulators, who are looking into whether they should fall under the bloc's dragnet on Big Tech companies.

The frenzy of AI deals and cloud partnerships reached another zenith Tuesday morning as Microsoft, Nvidia, and Anthropic announced a surprise alliance that includes a $5 billion investment by Microsoft in Anthropic — which in turn committed to spend at least $30 billion on Microsoft’s Azure cloud platform.