India, Dec. 18 -- The Delhi government on Wednesday substantially narrowed the scope of its planned ban on older vehicles from neighbouring states, announcing that the prohibition would now be enforced only during the most severe air pollution episodes. This rollback comes just a day after officials declared that no vehicle registered outside Delhi with emission standards lower than Bharat Stage VI (BS-VI) would be allowed to enter the city starting Thursday.

The final order, issued Wednesday, states that the restriction will apply exclusively when Stage 4 of the Graded Response Action Plan (Grap) is in force. Stage 4 is invoked when the Air Quality Index (AQI) surpasses 450, signifying "Severe Plus" conditions. This marks a notable shif...