A report in the Irish Mail on Sunday contains allegations from four whistleblowers – who are all private bus operators.
They claim they were asked to give kickbacks to unnamed Bus Eireann officials, in return for contracts.
However, the company says today's allegations are not new and have previously been proven to be untrue.
They say the claims date back to December 2012 when they emerged as part of an unsuccessful High Court challenge to Bus Éireann's right to run schools transport on behalf of the Department of Education.
