The chief executives of seven of the largest United States cloud computing and artificial intelligence companies sent a joint letter to congressional leaders Monday morning opposing the data center construction moratorium introduced last week by Senator Bernie Sanders and Representative Alexandria Ocasio-Cortez, and pledging a combined $42 billion in private investment over the next five years to expand transmission infrastructure, fund advanced nuclear projects and accelerate the deployment of behind-the-meter generation at large AI campuses.

The letter, addressed to Senate and House leadership and the chairs and ranking members of the Senate Energy and House Energy and Commerce committees, was signed by Andy Jassy of Amazon, Satya Nadella of Microsoft, Sundar Pichai of Alphabet, Mark Zuckerberg of Meta Platforms, Jensen Huang of NVIDIA, Sam Altman of OpenAI and Dario Amodei of Anthropic. The four-page document was released publicly at 11 a.m. Eastern time and posted on a newly created website, americancomputefuture.org, that the signatories described as a coalition for “responsible AI infrastructure.”

The letter framed the moratorium proposal as a self-inflicted strategic wound that would cede leadership in artificial intelligence to China and Gulf-state competitors at the precise moment when domestic AI capacity was most needed. “A two-year halt on new data center construction would not save a single kilowatt-hour on the grid this summer,” the executives wrote. “It would, however, hand a decade of accumulated American advantage in advanced computing to jurisdictions that face no such constraints, and it would do so on a timetable measured in months, not years.”

The $42 billion commitment was the most concrete offering in the letter and the element that congressional aides and industry analysts said would determine whether the document had the political effect its authors intended. Of that total, $18 billion would be directed to transmission line construction in priority corridors identified by the Federal Energy Regulatory Commission, $14 billion would be invested in small modular reactor projects through long-term power purchase agreements, and $10 billion would fund on-site generation and storage at hyperscaler campuses, including natural gas, fuel cells and battery installations sized to serve as grid resources during stress events.

Whether those commitments amount to new spending rather than a relabeling of previously announced capital plans was an immediate point of contention. A spokesperson for Sanders, Eleanor Briggs, said in a statement that the letter “is a confession dressed as a counteroffer.” “The companies are admitting that the grid cannot absorb what they have built, and they are asking Congress to thank them for proposing to fix the very problem they created, with money they were already planning to spend,” Briggs said. Ocasio-Cortez, in a brief statement posted to social media Monday, called the letter “a lobbying document, not a policy proposal,” and said the moratorium remained the cleanest path to forcing an honest national accounting of AI’s resource footprint.

The letter landed less than 48 hours after a weekend of widely reported inference throttling at the major cloud providers, an episode that the executives addressed directly and somewhat defensively in the document. They described the weekend’s capacity management as “evidence that the system works,” arguing that the hyperscalers had voluntarily reduced load in coordination with regional grid operators rather than waiting for involuntary curtailment. Critics responded that the framing inverted cause and effect — the system “worked” only because companies acknowledged, however quietly, that the grid could not have served their full demand.

Industry analysts saw the joint letter as an unusually unified posture from a group of companies that more often compete bitterly. “It is rare to see Andy Jassy and Satya Nadella co-sign anything, let alone a document that contains specific dollar commitments,” said John Reilly, a technology infrastructure analyst at Citi. “That tells you how seriously this industry is taking the political moment. They believe the moratorium has a non-trivial chance of passing the Senate, and they are trying to give wavering Democrats a reason to vote no.”

The political environment for the moratorium has shifted measurably since the bill’s introduction Thursday. Several moderate Senate Democrats, including senators from states with concentrated data center investment, have expressed concern over the weekend about the bill’s breadth, with one Virginia Democratic aide telling reporters that “a blanket moratorium is the wrong tool for a problem that needs surgical answers.” At least three Republican senators, however, have indicated through aides that they are considering supporting the legislation on energy security grounds, citing the war in Iran and rising household electric bills in their states. A senior Republican Senate energy staffer, who was not authorized to speak on the record, said the political logic of voting “with Sanders” against “Silicon Valley” was easier to explain to constituents this spring than at any time in recent memory.

The chairman of the Senate Energy and Natural Resources Committee announced Monday afternoon that the committee would hold hearings on the moratorium beginning April 1, with testimony scheduled from cloud company executives, utility chief executives, grid operators and consumer advocates. A separate hearing in the House Energy and Commerce Committee was tentatively set for April 3. A committee aide, Karen Loftus, said the chairman had received the joint letter and intended to “take its commitments seriously, but not at face value.”

Environmental groups offered cautious responses. Kavya Nair, vice president for policy at the American Council on Renewable Energy, said the $14 billion nuclear commitment was “directionally useful but not a substitute for the grid governance reforms this moment requires,” noting that small modular reactor projects had repeatedly slipped timelines and that none of the commercial designs under development in the United States had yet reached operational status. The Sierra Club’s energy program director, Hugh Patel, said the on-site natural gas component would lock in fossil generation at AI campuses for decades and was “the opposite of progress dressed up as compromise.”

Within the technology industry, the letter’s release produced its own internal frictions. Two people familiar with the discussions said NVIDIA had pushed for more aggressive language about Chinese competition while Anthropic and OpenAI had sought to include explicit acknowledgements that the industry’s resource consumption deserved scrutiny. The final text struck a compromise that some inside the signing companies privately called unsatisfying.

Markets reacted positively to the announcement. Shares of NVIDIA closed up 2.8 percent on Monday, Microsoft rose 1.4 percent and Alphabet gained 1.1 percent in a broader market that was otherwise flat. Constellation Energy and Vistra, two utilities with significant data center exposure, both rose more than 3 percent on expectations that long-term power purchase agreements with hyperscalers would expand.

The Sanders-Ocasio-Cortez bill was scheduled to receive its first committee markup on April 2, and aides to several senators said they expected the joint letter and the hearings that follow to substantially shape the legislation’s eventual fate. A spokesperson for Senate Republican leadership said no decision had been made on whether to bring the bill to the floor, and that any scheduling determination would await the conclusion of committee proceedings.