(Bloomberg) -- Libor, the benchmark underpinning more than $350 trillion of financial products, will be phased out by the end of 2021, as U.K. regulators and banks look to replace the scandal-tarred indicator with a more reliable system.

Andrew Bailey, the head of the Financial Conduct Authority, said Thursday that the rate isn’t sustainable because of a lack of transactions providing data. Libor became a byword for corruption after traders were caught manipulating the benchmark, leading to about $9 billion in fines and the conviction of several bankers.

“We do not think we will complete the journey to transaction-based benchmarks if markets continue to rely on Libor in its current form,” Bailey said in a speech at Bloomberg’s London headquarters. “Panel bank support for current Libor until end-2021 will enable a transition that can be planned and can be executed smoothly.”

The London interbank offered rate, or Libor, is behind securities including student loans and mortgages. The benchmark is the average rate a group of 20 banks estimate they’d be able to borrow funds from each other in five different currencies across seven time periods, submitted by a panel of lenders every morning. Its administration was overhauled in the wake of the scandal, with Intercontinental Exchange Inc. taking over from the then-named British Bankers’ Association with the aim of making the rate more transaction-based.

But the 58-year-old Bailey said the market supporting Libor -- where banks provide each other with unsecured lending -- was no longer “sufficiently active” to determine a reliable rate and alternatives must be found. For one currency and lending period there were only 15 transactions in 2016, he said.

Serious Question

“The absence of active underlying markets raises a serious question about the sustainability of the Libor benchmarks,” said Bailey, who is widely seen as a candidate to be the next governor of the Bank of England. “If an active market does not exist, how can even the best run benchmark measure it?”

The search for a new benchmark may lead to tighter swap markets, lower rates and richer attorneys as contracts need to be rewritten and adjusted to remove Libor.

“The impact of this decision from the FCA is to put uncertainty into all Libor-based swap rates,” said Peter Chatwell, head of European Rates Strategy at Mizuho International Plc in London. “The market will need guidance as to what a replacement could be and this will lead to increased volatility and possibly reduced liquidity in the near term.”

The FCA only started regulating Libor in 2013, the same year legislation was passed making it a criminal offense to take any misleading action in relation to financial benchmarks.

The FCA chief said the regulator has spent a lot of time persuading banks to continue submitting rates, something the agency has the power to enforce, but the lack of liquidity makes this impossible to maintain and leaves it open to manipulation.

However, he told Bloomberg in an interview Thursday the proposed change didn’t excuse the abuse of the benchmark that has seen five former bankers jailed in the U.K. and a number of others convicted in the U.S.

“The issues that we’re dealing with today do not in any sense excuse or mitigate what went on,” Bailey said. “Those who say that this demonstrates that what went on in the past is somehow understandable because the system was broken, I’m afraid that is not an argument that this justifies at all.”

The FCA has spoken to the panel banks over recent months about ending the use of Libor and how much time it would take to wind-down, Bailey said. While it would be tough, most said it could be done in four or five years, and the FCA has asked banks to continue submitting rates until the end of 2021.

Push from Authorities

Bailey said he could see a situation where there is more than one benchmark, with some including bank credit risk while others exclude that data. While discussions with banks and other users of Libor are at early stages, he said it may take a “push” from authorities to move the process forward at times.

“We’ve had no conversations about using capital tools,” Bailey said in response to questions after his speech. “But you can take it for granted that if we don’t see the progress that we need to see to hit this time scale, then in the broader sense there will be a ‘push’ from authorities.”

The development comes as a number of groups have been considering alternatives to Libor.

Bank of England Governor Mark Carney said earlier this month that Libor is no longer suitable. The central bank said in April that a swaps-industry working group had proposed replacing Libor in contracts with the Sterling Overnight Index Average, or Sonia, a near risk-free alternative derivatives reference rate that reflects bank and building societies’ overnight funding rates in the sterling unsecured market.

The bank had no further comment when contacted on Thursday.

Concerns have mounted in the euro area over Euribor, the benchmark interest rate for $180 trillion a year of intra-bank lending, as banks pull out of rate-setting panels in the wake of the Libor-rigging scandal. The European Central Bank acknowledges the shortcomings of the mechanism but wants the financial industry to take the lead in finding a solution.

In June, a U.S. government body, the Alternative Reference Rates Committee, recommended replacing Libor with a new, broad Treasuries repo rate, linked to the cost of borrowing cash secured against U.S. government debt.

Switzerland is replacing its own key swaps rate, TOIS, with a new benchmark on Dec. 29.

Asked whether this transition away from Libor should have happened earlier, Bailey said it would have been hard to predict five years ago that the world would still be in an environment of quantitative easing and low interest rates.

“I’m not criticizing the reforms, they were done with good intent and with a view that the market would return,” Bailey told Bloomberg. “We are where we are.”

(Updates with comments from interview with Bailey in seventh paragraph.)

--With assistance from Jill Ward and Paul Gordon

To contact the reporter on this story: Suzi Ring in London at sring5@bloomberg.net.

To contact the editors responsible for this story: Anthony Aarons at aaarons@bloomberg.net, Christopher Elser

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