Banking giant Credit Suisse said Thursday it will borrow $54 billion from Switzerland’s central bank, the latest move by authorities to calm investors and ease mounting fears of a global banking crisis.

The move to shore up Switzerland’s second-largest commercial bank saw its shares soar as markets reacted well in Europe and the United States. It was a marked reversal from a day earlier, when Credit Suisse shares slumped and intensified fears of a possible run on bank deposits after the collapse of two U.S. banks last week.

The news comes as Treasury Secretary Janet Yellen prepares to tell Congress later Thursday that the American banking system “remains sound.”

Markets responded well to the Swiss action, with futures up in London, Frankfurt and on Wall Street.

Credit Suisse shares settled to a gain of around 23% after an initial rise of 30%, while European bank shares recovered a bit across the board.

“These measures demonstrate decisive action to strengthen Credit Suisse as we continue our strategic transformation to deliver value to our clients and other stakeholders,” CEO Ulrich Koerner said in a statement that was published in the middle of the night in Zurich.

The Euro Stoxx Banks index, which tracks the continent’s biggest lenders, was up 1.5% in early trading while European bond markets, often seen as a safe haven for investors, also calmed.

Trading was volatile in Asian markets, however.

“What we’ve seen overnight is the Swiss central bank saying ‘No, we will not let this get into a disorderly collapse,’” John Gieve, a former deputy governor of the Bank of England, told BBC News.

The deal comes after Credit Suisse led a selloff in bank shares as its share price hit a record low Wednesday, fueling new fears about the health of global banks following the collapse of Silicon Valley Bank and Signature Bank in the United States.

Credit Suisse’s long-standing problems were compounded when its largest investor, the Saudi National Bank, said it could not provide more financial assistance because it was wary of regulatory checks that would kick in.

On Thursday, the Saudi bank’s chairman, Ammar Al Khudairy, said that the market turmoil in shares of the Swiss lender was “unwarranted.”

“If you look at how the entire banking sector has dropped, unfortunately, a lot of people were just looking for excuses,” Al Khudairy told CNBC’s Hadley Gamble. “It’s panic, a little bit of panic. I believe completely unwarranted, whether it be for Credit Suisse or for the entire market,” he said.

Thursday’s Credit Suisse action is the first major international bank to be given such a lifeline since the 2008 financial crisis, and the move could raise questions over how banks will navigate rising inflation across the world. Last month, Credit Suisse reported its largest annual loss since that crisis.

Problems at the bank, founded in 1856 and one of the biggest in the world, has shifted the finance world’s gaze from the U.S. to Europe.

SVB, the U.S. tech sector’s favorite lender, shut down last week, leading federal authorities to guarantee all its deposits. Two days later, New York regulators shut down Signature Bank, a big lender in the cryptocurrency industry.

Yellen will tell the Senate Finance Committee later Thursday that the American banking system is robust, as she becomes the first Biden administration official to face lawmakers over the SVB decision.

“I can reassure the members of the committee that our banking system remains sound, and that Americans can feel confident that their deposits will be there when they need them,” she is due to say, according to remarks released ahead of the session.

Political leaders in countries including Australia and South Korea have also sought to reassure investors that their banks are well-capitalized and not facing crisis.

“The problems in Credit Suisse once more raise the question whether this is the beginning of a global crisis or just another ‘idiosyncratic’ case,'” Andrew Kenningham of Capital Economics, a London-based economic forecaster, said in a research note Wednesday, before the Credit Suisse deal was announced.

While Credit Suisse has had its own issues distinct from the problems that felled SVB and Signature, analysts said higher interest rates in the U.S. and abroad have put pressure on the value of assets held by lenders around the world.

The Swiss bank, which has struggled with weak profitability in recent years, warned Tuesday that a recent stream of customers pulling their money out had slowed down but “not yet reversed.” The acknowledgment coincided with the disclosure that Credit Suisse had found “material weaknesses” in its financial reporting for 2021 and last year.

The bank has faced one scandal after another in recent years. It was convicted in connection with a money laundering plot involving a drug ring last summer. And it has had substantial entanglements with a collapsed hedge fund and a bankrupt British lender.