COMPLACENCY remains the biggest threat to the world’s financial markets a decade after the start of the Crash, Lord Darling has warned.

The former Labour Chancellor said there was a danger of forgetting the lessons of the past.

“In a few years’ time, when institutional memories start to fade and the people around have all gone and retired, then that’s where the risk occurs,” he said.

Lord Darling also revealed he had been shaken “to the core” by the “most scary moment” of the economic crisis, as he was told RBS would run out of money within hours.

The collapse of the then world’s biggest bank would have caused “blind panic”, he said.

Ten years ago on Wednesday, the French bank BNP Paribas triggered the worst recession since the 1920s by freezing three funds exposed to US sub-prime mortgage bonds.

It was the first admission by a major bank that no one knew what such bonds were worth, and led to a global credit crunch as institutions stopped lending to other bondholders.

A month later, there was a run on Northern Rock, and a year later the American bank Lehman Brothers finally collapsed because of its exposure to the sub-prime market.

Four weeks later, the UK Government was forced to bail out RBS, Lloyds TSB and HBOS.

Lord Darling, a former Labour MP for Edinburgh, told BBC Radio 4’s Today programme he had been pulled out a meeting of European finance ministers by a call from RBS.

He said the bank’s then chair, Tom McKillop, told him the bank was “haemorrhaging money”.

He said: “Remember this was not only the biggest in the world, it was about the same size as the entire UK economy.

“I said to him: ‘How long can you last?’ And what he said to me shook me to the core. He said: ‘Well we’re going to run out of money in the early afternoon.’”

The UK government still owns a 71 per cent stake in RBS.

Lord Darling said that if the bail-out had failed, not even the IMF could have helped.

However then PM Gordon Brown “phoned round all his counterparts in the big economies and said 'Look, you've got the same problem, you need to be doing the same thing too'.

"All countries acted together in a way that you very rarely see but it did actually contain it - although as we well know we are living with the aftermath of that financial and economic crash 10 years later and it’s by no means played out."

Former US Treasury Secretary Jack Lew said resistance to tougher banking regulation imposed after the Crash was now a growing problem.

He said: “One thing I worry about is that the memory of the financial crisis, as we approach the 10-year mark, is starting to fade a bit.

“What Wall Street reform did was for the first time since the Great Depression gave us the ability to have tools where we could deal with an evolving financial system to have the safeguards that we need.

“Even before [the US presidential] election you saw a great pushback among many, saying this has gone too far.”

However former Bank of England deputy governor Sir John Gieve told the BBC he did not foresee a rerun of 2008 because banks now had more reserves and were better regulated.

“The main debt which threatens a sudden break is probably in the far east and China which has been running a credit binge now for a decade and is showing signs of over-extension.”