In early December, UBS realised it had a problem. As the credit markets continued to slump, the Swiss bank concluded that the value of its investments linked to US subprime mortgages had dropped by another $10bn.

It was under pressure to disclose the additional losses as quickly as possible. But executives were worried the writedown would raise concerns about the bank’s capital position, undermining confidence in its private banking business. It needed fresh capital. Executives drew up a list of seven large sovereign investors that might be interested in backing the bank, and started calling.