(2) Where an official journey by train is cancelled in public interest, cancellation and reservation charges, as the case may be, will be reimbursed to the government servant from the budget head relating to office contingencies directly by the department/office concerned in which he is employed, on furnishing a certificate to be recorded by the Controlling Officer, or by the government servant himself if he is the Controlling Officer in respect of his own travelling allowance, that the journey has been cancelled in public interest.