A thick layer of toxic foam covered the river Yamuna in Delhi's Kalindi Kunj area ahead of Chhath Puja raising concerns from citizens and politicians.
The foam, which appeared on Friday also prompted authorities to spray chemical defoamers to address the issue.
Bharatiya Janata Party leader Shehzad Poonawalla blamed the Aam Aadmi Party government in the national and former Chief Minister Arvind Kejriwal for the pollution. He also accused Kejriwal of making Delhi a "gas chamber".
"On the next day of Diwali when we are here at Yamuna ghat, we can see a thick layer of foam on the river. The reason behind this foam (on the river) here is the corruption done by Arvind Kejriwal and Aam Aadmi Party. Now before Chhath Puja, they are sprinkling chemical defoamer," Poonawalla said.
A Delhi Jal Board team has been involved in cleaning the river and spraying chemicals into it since last week to remove the foam.
On Friday, Delhi CM Atishi announced a public holiday on November 7 for Chhath Puja celebrations.
The air quality in the national capital on Sunday again deteriorated to "very poor" category. The Air Quality Index in New Delhi on Sunday was 369, according to the data from the Central Pollution Control Board.
An AQI reading between 0 and 50 is considered 'good', 51 to 100 is considered 'satisfactory', 101 to 200 is considered 'moderate', 201 to 300 is considered 'poor', 301 to 400 is considered 'very poor' and 401 to 500 is considered 'severe'.
On Saturday the air quality had improved from the previous day while still being in the poor category. On Friday, the AQI in the national capital was 359 placed under the "very poor" category while on Saturday it was recorded at 294.