The Chair of the Public Accounts Committee says there is no way Angela Kerins and Frank Flannery can escape taking questions about the Rehab controversy.
Last night the PAC gave the group's two former executives two weeks to indicate whether or not they will appear.
The PAC will also write to individuals at the HSE, and other State bodies that may have given funding to Rehab, asking them to come forward.
The Committee Chair says that by the end of that fortnight the PAC will have prepared a submission for an application for compellability, to be made to the Committee on Procedures and Privileges.
He's warned that the CPP could take some weeks to adjudicate, and might need to take outside legal advice before advising the PAC on what action it can take.
Chairperson John McGuinness told Newstalk's Breakfast Ms Kerins and Mr Flannery should co-operate now.
He says Angela Kerin's doesn't have to attend within two weeks, just state her intentions while Frank Flannery's reasons for not attending do not stand up:
Mr. McGuinness says his committee needs to conclude its work, but cannot do so without the information they have requested from Angela Kerins and Frank Flannery.