WASHINGTON, May 5 (Reuters) - U.S. officials could lay out as soon as Wednesday guidelines for how banks can repay taxpayer bailout funds, sources familiar with administration thinking said on Tuesday.

One key condition is expected to be that banks are able to participate in the credit markets without the help of government facilities, such as the Federal Deposit Insurance Corp's debt guarantee program, the sources said, speaking anonymously because the guidelines have not been made public. (Reporting by Karey Wutkowski; editing by Carol Bishopric)