Mumbai International Airport Ltd (MIAL) has proposed moving flights that serve 14 international destinations from Chhatrapati Shivaji Maharaj International Airport (CSMIA) to Navi Mumbai International Airport (NMIA) while Terminal 1 is being redeveloped. The move aims to ease congestion and support the terminal's reconstruction.

Foreign airlines oppose the proposal, calling it "unilateral" and warning that forced relocations would disrupt commercial schedules. They say MIAL did not consult them on the relocation plan, and splitting operations between CSMIA and NMIA could create logistical challenges. NMIA user charges are up to 3.5 times higher than at CSMIA, adding to concerns.

Flights may shift to NMIA from March 28, 2027. Domestic carriers account for about three million of MIAL's five-million passenger reduction target.

The Airline Operators Council (AOC) has urged the Ministry of Civil Aviation (MoCA) to confirm historical airline slots for Summer 2027 and set a deadline of November 5 for the Slot Allocation List (SAL). Indian carriers have agreed to a phased shift of international operations from December 2026, but foreign airlines remain hesitant about transitioning to NMIA.

The redevelopment of Terminal 1B was initially scheduled to begin in January 2027. MIAL proposed reducing weekly international operations at CSMIA by 33% from October 26. The AOC has written to MoCA seeking intervention in the dispute and adherence to IATA's slot calendar and MoCA's 2013 guidelines.