New Delhi: India's top three telecom operators - Reliance Jio, Bharti Airtel and Vodafone Idea - have jointly written to the Mumbai Metro Rail Corporation (MMRCL) over a spat with ACES India, the company which has the contract for offering in-building solutions (IBS) for network connectivity for commuters.

The telcos said ACES India has asked them to pay exorbitant rental rates for the equipment they will install for connectivity. They said till the time a deal is reached over revised rentals they are willing to offer connectivity on a free-of-cost basis.

ACES India did not respond to ET's emailed queries till press time.

"It is reiterated that it would not be possible for us to provide IBS services at unviable rates offered by your selected partner ACES. In order to avoid inconvenience to your customers, we propose to offer connectivity to IBS network of ACES by installing our equipment," they said in a joint letter to MMRCL dated April 7.

"However, this offer of connectivity is purely on a free-of-cost basis till the time there is an agreement on terms and conditions for providing connectivity of IBS network to your selected partner ACES," the letter said.