# White House asks OpenAI, Anthropic to hold models back from UK's AI Security Institute

> The White House asked OpenAI and Anthropic to withhold new models from the UK's AI testers.

*US review first, UK access second. Anthropic appears to have gone along; the UK government says little has changed.*

By The FeaturedDaily Desk · FeaturedDaily
Canonical: https://featureddaily.com/news/white-house-openai-anthropic-uk-ai-security-institute

The White House has asked OpenAI and Anthropic not to share new AI models with the UK's AI Security Institute (AISI) until the US government has tested them first, Politico's Sophia Cai and Joseph Bambridge reported on 24 September 2026, citing a senior administration official and a person familiar with the matter. A British official confirmed the report to Bloomberg the next day.

> Because they're American companies and this has been our policy with every new frontier model that comes out,
> — [Politico](https://www.politico.com/news/2026/09/24/white-house-asks-openai-and-anthropic-to-hold-new-models-from-uk-testers-until-u-s-review-01091769), 2026-09-24

## What happened

The request came from the Office of the National Cyber Director, part of the White House. It is a policy position, not a public rule, order or statute. OpenAI declined to comment to Bloomberg; Anthropic declined to comment to Politico; the White House did not respond to either outlet.

Anthropic appears to have gone along already, Politico reported. Claude Mythos 5.1, launched 1 September 2026, was restricted to a set of US organisations. Anthropic's own announcement said it was 'coordinating with the US government to expand access to a broader set of domestic and international partners as quickly as possible.' AISI was not given access to test the model before release.

## AISI's response

AISI director Henry de Zoete addressed the gap in a letter to the House of Commons Business and Trade Committee on 15 September 2026: 'We maintain strong relationships with all frontier AI developers and continue to have prerelease access to some of the world's most capable models,' he wrote, pointing to its evaluation of OpenAI's GPT-6 Astra before its release. A UK government spokesperson told Politico: 'These risks do not stop at national borders and no country can tackle them alone.'

AISI reports £66m in annual funding, priority access to more than £1.5bn of compute and over 100 technical staff. Politico reported that the US Center for AI Standards and Innovation, the body Washington is asking labs to prioritise, has no permanent director and only a few dozen technical staff.

## Timeline

| Date | Event |
| --- | --- |
| 1 Sep 2026 | Anthropic launches Claude Mythos 5.1, restricted to US organisations |
| 15 Sep 2026 | AISI director Henry de Zoete writes to the Commons Business and Trade Committee on the access gap |
| 22 Sep 2026 | UK parliament summons OpenAI, Anthropic, Google DeepMind and Meta to a 13 October hearing |
| 23–24 Sep 2026 | Burnham and Miliband pitch AISI's role at the UN; Trump rejects coordinated global AI rules |
| 24 Sep 2026 | Politico reports the White House's request |
| 25 Sep 2026 | A British official confirms the report to Bloomberg |

## Context and what's next

The request lands the same week Prime Minister Andy Burnham used the UN General Assembly to describe AISI as working 'hand in glove with the U.S. and the leading labs on AI safety' and called for 'a single set of global principles and standards'. President Trump, at the same UN meeting, rejected coordinated global AI governance as a 'globalist scheme'.

UK MPs had already been pressing the access question before this story broke. On 22 September, the Commons Business and Trade Committee summoned OpenAI, Anthropic, Google DeepMind and Meta to a hearing on 13 October, with AISI's de Zoete giving evidence the same day. Committee chair Liam Byrne said 'voluntary self-regulation is unlikely to be a sustainable safeguard for the future'.

Separately, this year's tension between Anthropic and the Trump administration predates this story: Trump ordered federal agencies to stop using Anthropic's products on 27 February 2026, and the Commerce Department briefly blocked foreign nationals from accessing Anthropic's Mythos 5 and Fable 5 models on 12 June 2026, before restoring access to some US organisations.

## Key takeaways

- Politico reported on 24 September 2026 that the White House asked OpenAI and Anthropic to hold new models back from the UK's AI Security Institute (AISI) until the US tests them first.
- A British official confirmed the report to Bloomberg on 25 September; OpenAI, Anthropic and the White House declined to comment or did not respond.
- Anthropic's Claude Mythos 5.1, launched 1 September, was already restricted to a set of US organisations — the first real-world instance of the policy.
- AISI director Henry de Zoete says the institute retains prerelease access to other models, including OpenAI's GPT-6 Astra, tested before its release.
- OpenAI, Anthropic, Google DeepMind and Meta are due before UK MPs on 13 October over exactly this kind of access gap.

## FAQ

### What did the White House ask for?
That OpenAI and Anthropic hold back new AI models from the UK's AI Security Institute until the US government tests them first — reported by Politico on 24 September 2026.

### Has a model already been affected?
Yes. Anthropic's Claude Mythos 5.1, launched 1 September 2026, was restricted to US organisations and not given to AISI for testing.

### Is this now UK law or US law?
No. It is a policy position from the White House's Office of the National Cyber Director, not a published directive, statute or executive order.

### What happens on 13 October?
OpenAI, Anthropic, Google DeepMind and Meta are due before the Commons Business and Trade Committee, with AISI director Henry de Zoete giving evidence the same day.

## Sources

- [White House asks OpenAI and Anthropic to hold new models from UK testers until US review](https://www.politico.com/news/2026/09/24/white-house-asks-openai-and-anthropic-to-hold-new-models-from-uk-testers-until-u-s-review-01091769) — Politico, 2026-09-24
- [Trump Tells OpenAI, Anthropic to Withhold Models From UK Agency](https://www.bloomberg.com/news/articles/2026-09-25/trump-tells-openai-anthropic-to-withhold-models-from-uk-agency) — Bloomberg, 2026-09-25
- [Donald Trump tells OpenAI, Anthropic to withhold models from UK agency](https://www.business-standard.com/world-news/donald-trump-tells-openai-anthropic-to-withhold-models-from-uk-agency-126092501029_1.html) — Business Standard (Bloomberg), 2026-09-25
- [Introducing Claude Fable 5.1 and Claude Mythos 5.1](https://www.anthropic.com/claude-fable-and-mythos-5-1) — Anthropic, 2026-09-01
- [About the AI Security Institute](https://www.aisi.gov.uk/about) — AI Security Institute, 2026-09-26
- [OpenAI and Anthropic summoned to parliament on fears UK AI rules 'not fit for future'](https://www.cityam.com/openai-and-anthropic-summoned-to-parliament-on-fears-uk-ai-rules-not-fit-for-future/) — City AM, 2026-09-22
- [OpenAI and Anthropic could withhold new AI models from UK's AI Security Institute](https://www.itpro.com/security/openai-and-anthropic-snub-uks-ai-security-institute-on-new-model-testing) — IT Pro, 2026-09-25
- [Trump orders federal agencies to stop using Anthropic as dispute escalates](https://www.aljazeera.com/news/2026/2/27/trump-orders-federal-agencies-to-stop-using-anthropic-as-dispute-escalates) — Al Jazeera, 2026-02-27
- [Judge temporarily blocks Trump administration's Anthropic ban](https://www.npr.org/2026/03/26/nx-s1-5762971/judge-temporarily-blocks-anthropic-ban) — NPR, 2026-03-26
- [Anthropic disables Fable and Mythos AI models after U.S. government bars it from giving foreigners access](https://fortune.com/2026/06/13/anthropic-disables-fable-mythos-export-controls-national-security-threat/) — Fortune, 2026-06-13
- [Federal appeals court rules Pentagon's blacklist of Anthropic was legal](https://www.cnn.com/2026/09/25/tech/anthropic-pentagon-blacklist-dc-ruling) — CNN, 2026-09-25