NSW Transport Minister Andrew Constance is locked in a standoff with the Turnbull government over relaxing a cap for regional aircraft at Sydney Airport during peak hours, accusing Nationals leader Barnaby Joyce of "being completely obstinate".

In an escalation of his tussle with Canberra, Mr Constance said NSW was spending $100 million on upgrading regional airports yet the federal government was unwilling to follow suit to improve air services to towns in the bush by amending legislation.

He wants the federal government to alter the Sydney Airport Demand Management Act to allow for extra slots to be set aside for regional aircraft.

A state parliamentary inquiry recommended more than two years ago for the federal government to improve access to Australia's busiest airport for regional planes by relaxing the cap on landings or takeoffs for small, turboprop aircraft.