Indian operators Bharti Airtel and Vodafone Idea are preparing for a possible battle with the country’s Department of Telecommunications (DoT) over a demand for additional levies totalling INR94.5 billion ($1.1 billion), The Economic Times (ET) reported.

The regulator is apparently unwilling to negotiate on the latest sum, the newspaper wrote.

Earlier this week Vodafone Idea filed a petition with the Supreme Court challenging the DoT’s adjusted gross revenue (AGR) calculation, arguing the demand exceeds the court’s ruling in 2020 and threatens its financial survival.

The operator added a significant part of the AGR demand is covered by the ruling.

The high court prohibited reassessment in the judgement, the petition stated. The operator reportedly also questions the DoT’s revised calculations covering liabilities up to fiscal 2019, following its merger with Idea Cellular in August 2018.

Of the total demand, the petition declares INR2.7 billion relates to the post-merger entities (Idea Group and Vodafone Idea) and INR5.7 billion covers pre-merger Vodafone Group liabilities.

In June, the Indian government, the operator’s largest shareholder, suggested a number of measures to keep Vodafone Idea from going bust.

Its outstanding regulatory liabilities total nearly INR840 billion.