WASHINGTON (AP) - The Treasury Department is exploring the idea of issuing two new types of securities as a way of expanding the government's means of financing operations.

One of the securities would offer a floating interest rate rather than a fixed rate. The other would allow for securities to be auctioned with negative yields, which essentially allows investors to pay the government for the privilege of buying those securities.

Mortgage giants Fannie Mae and Freddie Mac have had success selling floating-rate securities.

Treasury officials say their bond advisory committee has recommended both instruments. They expect to make a decision in May.

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