Anthropic is to brief the global finance watchdog on the implications of its Claude Mythos AI model, whose potential threat to cyber defences has alarmed experts.

The US startup will discuss Mythos with the Financial Stability Board (FSB), which is chaired by the governor of the Bank of England, Andrew Bailey.

Anthropic has declined to release Mythos publicly after announcing the AI model had advanced capabilities in highlighting previously unknown flaws in IT systems that could be used by hackers.

Instead, the company has given access to Mythos to a group of tech companies and banks, including Apple and JP Morgan, to help them identify any weaknesses that the AI model may locate.

An FSB spokesperson confirmed the plan, saying the body “welcomes engagement with Anthropic and other firms on emerging and frontier risks to global stability”.

The UK’s AI Security Institute (AISI), which assesses advanced AI models, issued an updated appraisal of Mythos last week after scrutinising the version that has been released to banks and tech companies. It said the latest iteration it had seen represented a “notable capability jump” even on the preview version it had tested the previous month.

The AISI said the latest version of Mythos had completed a previously unsolved cybersecurity test, called “cooling tower”, in three out of 10 attempts. This was a first for any model tested by the AISI.

“Frontier AI’s autonomous cyber and software capability is advancing quickly: the length of cyber tasks that frontier models can complete autonomously has doubled on the order of months, not years,” the AISI said.

It added that it was developing new, tougher hacking tests to keep track of AI models’ progress.

The FSB monitors and makes recommendations about the global financial system and includes officials from leading economies including the US, the UK, Australia and China. Its steering committee includes senior central bank and finance ministry officials.

This month, the International Monetary Fund said financial stability risks were rising owing to “fast-moving” developments in AI, and called for a coordinated response.

“Cyber risk does not respect borders. As AI capabilities spread across countries, inconsistent oversight could weaken a globally interconnected system,” the IMF said in a blog post.

Last month, the chief executive of Goldman Sachs, David Solomon, said he was “hyper-aware” of the capabilities of Mythos, while his JP Morgan counterpart, Jamie Dimon, said AI had made cyber defence “harder” although it could ultimately help companies defend themselves against hackers.

Other experts have also sought to temper fears over Mythos, arguing that it represents an evolution in cyber threats rather than a revolution. Cybersecurity experts say that most breaches still come from well-established risks such as weak authentication and already known vulnerabilities that have not been patched.

When asked about news that the FSB would be assessing the risks of Mythos at the City Week conference in London, the Financial Conduct Authority chief executive, Nikhil Rathi, said AI developments had been a “significant topic of conversation” at the IMF meetings in Washington last month.

He said Bailey was “engaged” on the issue and that there was cooperation taking place with US authorities. Rathi also pointed to guidance released by UK regulators and the Treasury last week, which directed firms to “double down” on “core cyber hygiene”.

That meant “having looked at your legacy systems, having good detection mechanisms, having good governance in place, thinking about how you recover, thinking about your insurance”, he said.

Rathi added: “Anthropic has acted fairly responsibly in engaging with authorities” internationally on the risks of its AI.

Anthropic has been approached for comment.