This is the basic promise behind the "Treaty on the Non-Proliferation of Nuclear Weapons" (NPT).

https://en.wikipedia.org/wiki/Treaty_on_the_Non-Proliferatio...

In the text of the treaty there are promises to NPT signatories, such as:

Article IV "1. Nothing in this Treaty shall be interpreted as affecting the inalienable right of all the Parties to the Treaty to develop research, production and use of nuclear energy for peaceful purposes without discrimination and in conformity with articles I and II of this Treaty."

https://en.wikisource.org/wiki/Nuclear_Non-Proliferation_Tre...

But the hard reality of U.S. nuclear politics in regard to other countries can be read here:

"The Nuclear Fuel Cycle and The Bush Nonproliferation Initiative"

https://www.iaea.org/sites/default/files/neff.pdf

"The world’s leading nuclear exporters should ensure that states have reliable access at reasonable cost to fuel for civilian reactors, so long as those states renounce enrichment and reprocessing."

"The 40 nations of the Nuclear Suppliers Group should refuse to sell enrichment and reprocessing equipment and technologies to any state that does not already possess full-scale, functioning enrichment and reprocessing plants."

For example when United Arab Emirates wanted to build the Barakah nuclear power plant, (supplied by Korea Electric Power Corporation, not by an U.S. company), it had to sign an the Section 123 Agreement with United States of America. As part of the agreement, the UAE committed to forgo domestic uranium enrichment and reprocessing of spent fuel.

https://en.wikipedia.org/wiki/U.S.%E2%80%93UAE_123_Agreement...

To be fair, it's not only U.S. who want's the control access to nuclear technology and nuclear materials. For example India wanted to become a member of Nuclear Suppliers Group for a long time. As of 2019, China has thwarted every attempt of India's inclusion into NSG and has made it clear that status quo will remain citing "lack of consensus" among NSG members.

https://en.wikipedia.org/wiki/Nuclear_Suppliers_Group#India

Another example is South Korea. South Korea is constrained in its nuclear power policy by the 1974 Korea-US Atomic Energy Agreement. Only in November 2025 did the USA formally affirmed support for South Korea’s civil uranium enrichment and spent fuel reprocessing for peaceful uses.

https://www.armscontrol.org/act/2025-12/news/us-supports-sou...

https://world-nuclear.org/information-library/country-profil...

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