Citigroup Inc said on Sunday some 99 percent of its stock was tendered in an exchange offer for publicly held securities, in a key step toward giving the U.S. government a 34 percent equity stake in the bank.

Citigroup said preliminary results showed about $20.3 billion worth of publicly held convertible and nonconvertible preferred and trust preferred securities were tendered in the exchange offer.

The bank will issue 5.83 billion common shares to the public exchange offer participants, it said.

The exchange offer expired at 5 p.m. New York time on Friday.

The bank said it also expects to complete a further exchange with the U.S. government of $12.5 billion of its preferred stock. In total, about $58 billion of preferred and trust preferred securities would have been exchanged to common stock as a result of the completion of various exchange offers.

(Reporting by Paritosh Bansal; Editing by Christian Wiessner)