Authorities in the Indian capital on Monday introduced the "odd-even" car rationing scheme in a bid to cut hazardous air pollution shrouding the city.
Officials said cars with even and odd number plates will be allowed on roads on alternate days until November 15.
It's still unclear if the scheme, which was introduced in 2016 and 2017, was effective in combatting air pollution.
Uber and Ola, however, have been exempt from the plan, with the ride-hailing firms announcing they wouldn't hike prices during the period.
Meanwhile, all schools in the city have been ordered to shut down, and construction work stopped.
A government monitor on Sunday showed air quality had hit 494 on a scale of 500.

Palestinian teen shot dead in Israeli West Bank raid, Wafa reports
Libya says 17 migrants perish at sea, nine missing feared dead
Israel begins intercepting Gaza aid ships far from shores, army radio says
Trump urges Iran to sign a deal and discusses prolonged blockade
Seven people die in hospital wall collapse in southern India