TL;DR

Over 70 peers and MPs have written to Downing Street, asking the prime minister to get behind legislation that would outlaw artificial superintelligence, and to use Britain’s G20 presidency next year to build an international bloc around it. The government has already said the bill is not the right vehicle. The letter follows a fortnight in which two Anthropic insiders put the odds of human extinction from AI above one in ten.

Who signed

The signatory list is the point. Fifteen former ministers put their names to it, alongside Robin Butler, once the country’s most senior civil servant. John McDonnell and other senior Labour figures signed, as did Conservatives, Liberal Democrats and SNP members. The range runs from the broadcaster Floella Benjamin to Arlene Foster, formerly Northern Ireland’s first minister, and Zac Goldsmith, a Conservative environment minister until recently.

Their target is legislation the Labour MP Alex Sobel laid before the Commons last Tuesday, which would prohibit anyone building artificial superintelligence: a system, none of which yet exists, capable of beating humans across most domains. Sobel wants “a clear framework where superintelligent AI cannot be created”, and argues the labs have been candid that they are chasing exactly that while conceding it carries extinction risk.

External backing comes from the Nobel laureate and anti-proliferation campaigner Beatrice Fihn, Berkeley’s Stuart Russell, and Control AI, a lobby group bankrolled by Jaan Tallinn of Skype. In Washington, Bernie Sanders is pushing an equivalent measure.

The obvious objection

A prohibition binding Britain alone changes little, given that the frontier labs sit in America and China. The parliamentarians accept this, which is why the G20 ask matters more than the domestic clause. A government spokesperson said ministers do not think the bill’s measures are “the right approach”, but left the door ajar to “additional targeted interventions” on national security grounds later.

Looking forward

This lands beside the Joint Committee on Human Rights report and follows the Cabinet Office’s refusal of an emergency shutdown power. Three separate parliamentary attempts to legislate on AI have now met the same departmental resistance in under a fortnight. Elon Musk called the week’s warnings a “psyop”; UK businesses will note that the pressure is coming from ex-ministers, not activists.