Eight accounts, all newly created around 21 March, bet a total of nearly $70,000 (£52,000) on there being a ceasefire. They stand to make nearly $820,000 if such a deal is reached before 31 March.

An account that made the same bet was created shortly before the US struck Iran on 28 February. It also placed a winning bet on those strikes, which raised similar questions around insider trading, and so far has bet on nothing else.