The Supreme Court on Friday refused to modify its earlier order banning the sale of firecrackers in Delhi and the National Capital Region till November 1. The ban will be in effect till further orders.

“We will ascertain after Diwali whether there has been a difference in pollution levels,” the court said.

The bench stuck to its decision while hearing a plea by a group of traders, who had challenged the court’s October 9 order that barred the sale of firecrackers during Diwali. The court said it would first study the difference in air quality in the region, which is prone to high levels pollution.

The traders had moved court on Wednesday saying they had renewed their licences and had already bought stock to sell during Diwali. They said they bought firecrackers after the Supreme Court, in September, said that a complete ban would be “extreme” and allowed 500 temporary licences to be issued before Dussehra and Diwali.

Although crackers are not the only pollutants in Delhi-NCR, the air quality worsens to frightening levels the morning after Diwali, as seen in 2016.