Goldman Sachs Group Inc. has reportedly offered the first bitcoin-backed lending facility, a significant step for a central U.S. bank to speed up the acceptance of cryptocurrencies on Wall Street. A Goldman spokesman said the secured lending facility lends cash backed by bitcoin owned by the borrower. After soaring prices and popularity dented years of resistance, Wall Street banks are adding to their cryptocurrency offerings. Goldman Sachs traded bitcoin options over-the-counter for the first time in March and has a digital asset team. For Goldman, the step marks the entry into a new line of business.