Mont. Code Ann. § 53-1-106

If a treaty in effect between the United States and a foreign country provides for the transfer, by exchange or otherwise, of convicted offenders to the country of which they are citizens or nationals, the governor may, on behalf of the state and subject to the terms of the treaty, authorize the director of the department of corrections to consent to the transfer or exchange of offenders in Montana institutions and take any other action necessary to initiate the participation of this state in the treaty.