NOIDA, Nov. 29 -- Air quality in Noida and Greater Noida remained in the 'very poor' category on Friday, with air quality index (AQI) readings of 388 and 378, respectively, making them the most polluted cities in the country. Neighbouring Ghaziabad logged an AQI of 347, also 'very poor', according to Central Pollution Control Board (CPCB) data.

On Thursday, curbs under Stage 3 of the Graded Response Action Plan (Grap) were lifted as the air quality in Delhi -- taken as the base for NCR -- had marginally improved. Even then, AQI readings had stayed elevated at 391 in Noida, 381 in Greater Noida, and 358 in Ghaziabad, signalling persistent particulate stress.

Officials said winter dispersion conditions are yet to stabilise. Particulate so...