The demise of leading US investment banks last year focused regulatory attention on a crucial area of financial plumbing and sparked a debate about the future of the repurchase – or repo – market.

With big investment banks funding up to half of their balance sheets through repo last year, policy­makers and the industry are trying to cut the risk of relying on this type of short-term funding, which can evaporate quickly in a crisis and potentially roil a clearing bank.