Treasury Secretary Janet Yellen on Thursday told a Senate panel that the U.S. financial system is on solid footing following the second- and third-largest bank collapses in the nation’s history.

Her remarks come after a bank run on Silicon Valley Bank (SVB) and Signature Bank forced federal regulators to close the banks and protect all deposits in an effort to preserve public confidence in the U.S. banking system. 

“I can reassure the members of the committee that our banking system is sound, and that Americans can feel confident that their deposits will be there when they need them,” Yellen told the Senate Finance Committee. “This week’s actions demonstrate our resolute commitment to ensure that our financial system remains strong and the depositors’ savings remain safe.”

Regulators ensured that the banks’ clients got their deposits back using a fund paid for by fees on banks. The Fed, meanwhile, launched an emergency lending program to help banks weather a surge in withdrawals. Yellen noted Thursday that the unprecedented action did not protect shareholders.  

SVB faced massive unrealized losses on its long-term treasury bond investments due to the Federal Reserve’s interest rate hikes. The bank’s tech industry and venture capital clients rushed to withdraw their money when it became clear SVB faced the threat of insolvency. 

When pressed by Sen. Mike Crapo (R-Idaho), the committee’s ranking member, Yellen acknowledged that interest rate hikes forced SVB to sell large amounts of assets at a loss, but didn’t say that the U.S. financial system faces a broader liquidity crisis.

The global economy is staring down warning signs following the bank failures. Swiss investment bank Credit Suisse faces liquidity issues, while Moody’s is weighing downgrading the credit rating of six regional U.S. banks.

Short-term treasury yields plummeted earlier this week as investors flocked to safer assets. The ICE BofA MOVE index, which measures bond market volatility, has risen to its highest level since the 2008 financial crisis.