STORY: Citigroup Inc CEO Jane Fraser expressed confidence in U.S. banks after a series of closures rattled investors and fueled in global financial markets.[CEO, Citigroup, Jane Fraser]'I don't think they need to go out right now because the banking system is pretty sound. And we're talking about a few banks. We heard it from the Chairman Powell today. This is not something that is spread across the entire banking system. This isn't like it was last time. This is not a credit crisis.'In the past two weeks, two U.S. banks collapsed, Credit Suisse Group AG CSGN.S was taken over by Swiss rival UBS Group AG and America's biggest banks agreed to deposit $30 billion in another ailing firm, First Republic Bank.Citi, the fourth-largest U.S. lender, was one of 11 major banks that threw a lifeline to First Republic last week, in an effort to help it buy time for restructuring.Fraser said Citi is not interested in buying First Republic and expects to get paid back the $5 billion of uninsured deposits her company contributed to the lender, which was intended as a mark of confidence.[CEO, Citigroup, Jane Fraser]'So despite this being quite a divisive environment that we're all operating in, this is an instance of the banks coming together and saying: 'Okay, what can we do here to support a system that we have confidence in?' And you don't put $5 billion into the system through the generosity of your own heart. You do it because you have confidence in the system itself.'