NEW DELHI: The Delhi government is likely to enforce the odd-even restrictions only during periods of spike in air pollution, Delhi Chief Minister Arvind Kejriwal , enthused by the "overwhelming" response of the people on the first day of the initiative, said today.Kejriwal explained that there would be a reassessment after the pilot plan ends on January 15 and that it would never be "permanently" implemented. It had assumed the form of a "movement" within few hours of its implementation from 8 AM in the morning, he said.The Chief Minister made the remarks after the commencement of the radical scheme, which is aimed at mitigating spiralling air pollution levels with the stipulation today that private cars bearing odd-registration plates can ply on city roads."This will go on till January 15. Then we will stop it and reassess. Nowehere in the world is the scheme enforced permanently. It is practically not possible. Whenever pollution levels spike this is used as a weapon," Kejriwal said.The Chief Minister said the restrictions may again be invoked for few days in the next 2-3 months if pollution level sees a jump. As per initial reports, the plan has been "quite successful" and people in the national capital have largely accepted the restrictions with an "open mind", Kejriwal said.Under the regulations, cars bearing odd-numbered registration plates shall ply on city roads today while those with even number plates, if taken out, will attract a penalty of Rs 2,000 under relevant sections of the Motor Vehicles Act. It will be vice-versa tomorrow.