(Reuters) -Two Democratic U.S. senators demanded information from Microsoft ( MSFT ) and Google about their cloud computing partnerships with artificial intelligence companies, expressing concern the arrangements could stifle competition in the cutting-edge industry.

U.S. Senators Elizabeth Warren of Massachusetts and Ron Wyden of Oregon, the ranking Democrats on the Senate banking and finance committees, respectively, asked Google for details about its partnership with AI startup Anthropic and Microsoft ( MSFT ) about its tie-up with ChatGPT creator OpenAI, according to drafts of the letters seen by Reuters.

"We are concerned that corporate partnerships within the AI sector discourage competition, circumvent our antitrust laws, and result in fewer choices and higher prices for businesses and consumers using AI tools," the senators wrote.

The letters seek how much the AI companies have paid the cloud providers, whether the deals give Microsoft ( MSFT ) and Google exclusive rights to license AI models, and whether the Big Tech companies have any plans to acquire their AI partners.

The U.S. Federal Trade Commission issued a staff report in January, before U.S. President Donald Trump took office, on a study into partnerships between Microsoft ( MSFT ) and OpenAI, Amazon ( AMZN ) and Anthropic, and Google and Anthropic but withheld information specific to the companies.

The report raised the possibility that one cloud service provider could acquire its AI partner, and said that at least one of the AI providers gave its cloud service provider advance notice of important decisions.

At least one of the agreements would prevent the AI company from launching new models on its own without releasing it via the cloud provider, the FTC said.