Mumbai International Airport Ltd (MIAL) said it won’t disturb slots for airlines this winter, a concession that follows mounting opposition from carriers to its plan to redevelop Terminal 1 and move some international flights to a new airport nearby.

The operator, run by Adani Airport Holdings Ltd (AAHL), will honour historical slot allocations through the winter schedule, it said in a statement after a meeting with the Airline Operators’ Committee on Tuesday.

Jeet Adani, director, and Arun Bansal, CEO of AAHL, met the airlines amid mounting opposition from airlines to MIAL’s redevelopment plans and its proposal to shift a portion of international operations to the upcoming Navi Mumbai International Airport (NMIA).

The International Air Transport Association (IATA) objected to the relocation in a September 9 letter to India’s civil aviation ministry, arguing that any shift should be voluntary, commercially viable and operationally feasible.

The airline lobby also called for consultation with carriers and for Navi Mumbai International Airport to be fully ready before traffic is moved.

Airlines have raised concerns about operational viability, a lack of consultation and disruption to established schedules. Some aviation experts have questioned the timing of the project, saying it could have waited until the new airport was prepared to handle international operations. Mumbai airport had previously indicated that demolition of T1B would begin Jan. 15, 2027.

What Now?

A joint working group of airport and airline representatives will spend the next two weeks drafting an implementation plan for the redevelopment, the operator said. It said carriers committed to backing the project and the rebalancing of traffic between the two airports from the summer schedule.

Mumbai airport pledged full support to any airline that opts to move to Navi Mumbai. The two sides will meet again on October 28 and, in the interim, will work through operational details with individual airlines’ network and slot teams.

Both parties reaffirmed their commitment to developing Mumbai’s airport infrastructure, the operator said.

Why The Redevelopment Is Contentious

The assurances come against the backdrop of a dispute over how Mumbai’s airport capacity should be managed while T1 is redeveloped.

MIAL had proposed shifting roughly a third of international passenger and cargo operations from Chhatrapati Shivaji Maharaj International Airport (CSMIA) to NMIA, prompting concerns among airlines over operational viability, consultation and the potential disruption to established schedules.

Aviation experts have also questioned the timing of the redevelopment, suggesting that it could have waited until NMIA was fully prepared to handle international operations.

Speaking to The Core, former Airports Authority of India official Vijai Agrawal acknowledged that T1’s infrastructure was outdated but argued that the redevelopment needed to be timed appropriately.

“The building part is outdated, I do agree. There is no issue,” Agrawal told The Core. “But this is to be timed.”

In a September 9 letter, IATA had objected to the proposed relocation, arguing that any transfer should be voluntary, commercially viable and operationally feasible. It also called for consultation with airlines and adequate operational readiness at NMIA before traffic is shifted.

MIAL’s redevelopment plans have also raised questions about the timing of the transition, with the airport operator previously indicating that demolition of T1B would begin on January 15, 2027.

Tuesday’s meeting offers some clarity on the immediate timeline, with MIAL committing not to disturb winter schedule slots and discussions on traffic balancing set to continue.

However, the joint working group’s recommendations and the October 28 meeting will be key to determining how the redevelopment and transition between the two airports will be implemented.