TL;DR

Dr Jade Leung is giving up her two full-time government jobs at the end of September for personal reasons. She has been AI adviser to the prime minister and, at the AI Security Institute (AISI), its chief technology officer. She will stay involved part-time as AISI’s vice-chair and as security adviser to the AI Taskforce. Downing Street will name a new AI adviser later.

What changes

The government announcement frames the move as a transition, not a departure. Leung keeps a formal role in AI safety and security policy through the two new posts. Alongside them she will take up a part-time fellowship at the Hoover Institution at Stanford University.

As AI adviser, according to the announcement, she helped set policy on advanced AI across public services, national security and growth. It also credits her with a central part in setting up AISI and building its technical research programme.

Andy Burnham, the prime minister, said the country was “better prepared” for AI because of her work. AI minister Kanishka Narayan listed specific achievements: building AISI into what he called a “world leading institution”, setting up the AI Growth Zones programme, and landing an AI deal with Ukraine.

Why it matters

Leung has been among the most visible technical voices in UK AI policy. In April she described AISI’s red-teaming findings publicly, saying every frontier model the institute had tested had exploitable weaknesses. As CTO she sat at the heart of the institute’s technical work, which is much of what the UK points to when it claims a lead on AI safety.

The timing is awkward. This week Burnham told the UN that Britain would lead on global AI standards, and AISI’s testing is a large part of what backs that pitch. Two senior posts now need filling at once. The announcement gives no date for a new adviser and does not say who will take over as AISI’s chief technology officer.

Looking forward

Leung stays inside the tent. The vice-chair and taskforce roles keep her expertise available, and continuity at the top of AISI may matter more than headlines suggest. The appointment to watch is the next prime minister’s AI adviser. Whoever it is will shape how Burnham’s government turns its international standards pitch into domestic policy, at a time when plans for a UK AI safety law have stalled.