The Prime Minister Tony Abbott has ordered cabinet ministers and top public servants to personally approve the airfares and hotel bookings of tens of thousands of bureaucrats as part of a crackdown on government travel costs.

Fairfax Media has learnt that on November 18, Mr Abbott issued a directive designed to clamp down on official travel by federal public servants, domestically and overseas.

Directive: Tony Abbott has issued new rules. Credit:Andrew Meares

He instructed all cabinet ministers to take personal responsibility for approving official travel by departmental officials, whether individuals or delegations, where the proposed cost exceeded $20,000. He directed that he must be consulted about any proposed travel, whether by an individual or a delegation, that exceeded $50,000.

Mr Abbott decreed that all public servants' travel costing less than $20,000 must be approved by departmental secretaries or agency heads and responsibility "should not be delegated below that level".