The growing demand by some states for a revenue share in those airports that are up for privatisation will be a dual test for the Union government on cooperative federalism and the trajectory of the mammoth National Monetisation Pipeline (NMP) programme. The demand, which was first made by Dravida Munnetra Kazhagam (DMK)-ruled Tamil Nadu and has been echoed by Chhattisgarh, where the Congress is in power, and Jharkhand, run by the Jharkhand Mukti Morcha — all the parties concerned are opposed to the Bharatiya Janata Party (BJP) — is a response to the plan by the Airports Authority of India