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The European Central Bank is about to turn the screws again on financial institutions by diving even deeper into negative interest rates.

Lenders including Deutsche Bank AG and UBS Group AG are bracing for another blow to their profitability after five years of sub-zero monetary policy. While the ECB’s strategy is to boost growth and inflation by lowering borrowing costs for companies and households, squeezing banks too much could hamper their ability to supply the credit that fuels the economy.

“The interest-rate policy is an enormous burden,” Christian Sewing, chief executive officer of Deutsche Bank, said at a conference in Frankfurt last week. “In the long run, negative rates ruin the financial system.”

Such pleas are unlikely to stop the ECB. It begins a two-day meeting on Wednesday to prepare stimulus to respond to risks including U.S. protectionism and Brexit. The most Sewing and rivals can hope for is accompanying measures to soften the blow.

The ECB’s deposit rate used to be the interest banks received for keeping their excess cash at the central bank overnight. Now at minus 0.4%, it has become a charge, one that Deutsche Bank says could cost it hundreds of millions of euros this year.

Many lenders already pass the charge onto corporate and institutional clients, but doing so with ordinary people -- whose savings are a key source of bank financing -- could prompt them to withdraw their cash.

“Retail is really a difficult area because then the trust comes in,” said Kees van Dijkhuizen, CEO of ABN Amro Bank NV.

So banks suck up the cost, at least until their profitability is eroded so much that they’re forced to retrench, hurting the economy. That’s the point known to economists as the reversal rate.

“Banks would have to reflect that on deposits, and that of course would create a big backlash,” former ECB Vice President Vitor Constancio told Bloomberg Television last week. “My personal view is we’re already close to the limit.”

Scope Ratings reckons euro-area banks have incurred 23 billion euros ($25 billion) of charges at the ECB since negative rates started in 2014, and are currently paying almost 7 billion euros a year. Return on equity is about 40 basis points lower than it would otherwise have been.

The ECB says the cost to lenders is small -- Executive Board member Benoit Coeure called it “peanuts” -- and outweighed by the profit on increased lending in a stronger economy.

That argument may be reaching its limit. President Mario Draghi said after July’s policy meeting that “we are not at the reversal rate” but “certainly there is a danger.” He’s considering whether to grant banks relief such as exempting some reserves from the charge -- a system known as tiering -- as the Swiss National Bank already does.

Bank stocks have rallied over the past month on the prospect that Draghi may offset at least some of the pain, with one key index up more than 7%.

Why ECB Will Stuff Free Money Into Bank Pockets Again: QuickTake

“Improvements like a tiering system are necessary to soften the detrimental consequences,” said Sewing. “But they don’t change the fundamental problem.”

Academic Arguments

Academics have also questioned the policy. A recent study published by the University of Bath found negative rates decreased lending. Federal Reserve Bank of San Francisco research concluded the introduction of the policy in Japan actually lowered inflation expectations.

Since the Bank of Japan started negative rates in 2016, bank stocks have been the third-worst performers among 33 industry groups on the Topix index, and doubts have started to creep in on the BOJ’s board over the impact of its extraordinary stimulus.

The Swiss National Bank’s minus 0.75% rate netted it 2 billion francs (1.8 billion euros) last year, but also plenty of criticism. Geneva-based private bank Pictet Group said the rate is at the “pain threshold.”

The Federal Reserve has steered clear of negative interest rates during the last downturn, even though the policy occasionally comes up as an option in the public debate. On Wednesday, U.S. President Donald Trump suggested it should be considered to bolster the economy.

According to Gilles Moec, chief economist at Axa SA, what the euro zone really needs is fiscal stimulus -- and while governments have so far been reluctant to go down that route, negative rates could help. The pressure from banks and pension funds in nations where the government has room to spend, such as Germany, could tip the balance toward action.

Negative rates are certainly a rising political issue. In Germany, Bavarian Premier Markus Soeder called for a ban on negative rates on deposits of up to 100,000 euros. Lenders rejected the idea, saying bans don’t ultimately help clients and could destabilize markets.

That debate reflects the reality that with subzero rates likely to last for years to come in Europe, the pressure is mounting on the financial industry -- and on governments -- to find a way to cope.

“It’s not good for banks, but one could argue, OK so what?,” Sergio Ermotti, CEO of UBS, said in Frankfurt last week. “The truth of the matter is the most profound changes that are really starting to affect society and the economy are the impact on the social system, and social savings, and this perception of people being totally concerned about their future.”

(Updates with comments from Trump in 18th paragraph.)

--With assistance from Catherine Bosley.

To contact the reporters on this story: Yuko Takeo in Tokyo at ytakeo2@bloomberg.net;Nicholas Comfort in Frankfurt at ncomfort1@bloomberg.net

To contact the editors responsible for this story: Malcolm Scott at mscott23@bloomberg.net, Paul Gordon

©2019 Bloomberg L.P.

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