Yields on some Treasury bills that are due to be repaid in early June jumped to over 7% Wednesday as investors shunned debt that is a risk of not being repaid if the U.S. Treasury Department runs out of cash.

The yields on bills due on June 1 were last at 7.198%, and briefly got as high as 7.310%. That is up sharply from Tuesday's close of 5.992%. Other bills due on June 6 also rose as high as 7.119%.

Some investors are avoiding bills that come due in June in case the U.S. debt limit is not raised.