State-owned helicopter service company Pawan Hans has agreed to help the Delhi government set up procedures to make it possible to aerially sprinkle water over the city to help pollutants settle. The quality of air in Delhi, the National Capital Region and in several North Indian cities remained in the “severe” category for the fourth day in a row on Friday.

The Delhi government said on Twitter that it was in talks with Pawan Hans for the purpose.

In a letter, Pawan Hans said it had carried out such tasks in the past, too. It suggested setting up a joint group of the government and its own team to work out a proposal. The company also asked the Delhi administration for a meeting to discuss the matter further.

Representatives of Pawan Hans are likely to meet Delhi government officials on Saturday, ANI reported.

In October, the Aam Aadmi Party government in Delhi had proposed the idea to the Centre and offered to pay to have water sprinkled over the city to control air pollution in winter. Delhi Environment Minister Imran Hussain had asked Union Environment Minister Harsh Vardhan to take up the matter with the Civil Aviation Ministry.

Vardhan on Wednesday said the Centre had asked Delhi to examine whether the method was cost-effective when compared to other simpler measures.

“If the government of Delhi thinks that sprinkling of water with helicopters is the most cost-effective measure, it is free to do so,” Vardhan had said. “I call for cost-effective measures since management of air pollution requires sustained actions over a long period of time to be effective.”