All government-aided and private schools in Delhi reopened on Monday after an early winter break with restrictions under Stage IV of GRAP revoked following some improvement in the city's air quality.

Outdoor sports activities and morning assemblies will not be held in schools for the next one week, according to an order issued by the Directorate of Education (DoE).

Schools in Delhi were shut down and a winter break was announced on November 8 amid rising pollution in the city and growing health concerns.

The DoE issued the order for resumption of classes for all students from pre-school to class 12 on Saturday in view of Delhi's improved Air Quality Index and there being no indication of a sharp degradation in the AQI in the near future.

Delhi experienced 'very poor' to 'severe' air quality for two weeks starting October 28 with a suffocating haze lingering over the city during the period.

Delhiites witnessed clear skies and abundant sunshine on November 11 and 12 as the air quality improved sharply just ahead of Diwali due to favourable meteorological conditions.

However, the respite was short-lived as people flouted the ban on firecrackers on Diwali on November 12, leading to a jump in pollution levels.

The Centre on Saturday removed stringent curbs, including a ban on construction work related to linear projects and the entry of polluting trucks into Delhi in view of a dip in air pollution levels due to favourable wind speed and direction.

These measures constitute the final stage -- Stage IV -- of the Centre's air pollution control plan called the Graded Response Action Plan (GRAP).

Air quality in Delhi and its suburbs deteriorated again on Monday after a marginal improvement a day ago with forecasts suggesting that a major relief is unlikely in the coming days.

The city's AQI stood at 338 at 8 am on Monday, deteriorating from 301 at 4 pm and 290 at 7 am on Sunday.

The 24-hour average AQI, recorded at 4 pm every day, was 319 on Saturday, 405 on Friday and 419 on Thursday.

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