(Recasts with pricing)

NEW YORK, June 11 (Reuters) - Citigroup Inc (C.N: Quote, Profile, Research) sold $1 billion in bonds without a government guarantee on Thursday, in a reopening of an existing issue first sold in May, said IFR, a Thomson Reuters service.

The notes were priced at 101.655 to yield 8.251 percent or 437.5 basis points over comparable U.S. Treasuries, IFR said.

The notes were sold in a reopening of the bank's 8.5 percent bond due 2019, which was originally sized at $2 billion.

The issue widened 4 basis points in the secondary market to 4.19 percent over Treasuries, according to MarketAxess.

The notes are not guaranteed under government regulator Federal Deposit Insurance Corp's temporary liquidity guarantee program. (Reporting by Caryn Trokie and Karen Brettell; Editing by Leslie Adler)