In an attempt to lessen air pollution in New Delhi, which gets worse during the winter, a temporary alternate-day travel scheme for cars using the odd- and even-numbered licence plates system was announced by Delhi government in December 2015. In addition, trucks were to be allowed to enter India's capital only after 11 pm, two hours later than the existing restriction. The driving restriction scheme was planned to be implemented as a trial from 1 January 2016 for an initial period of 15 days. The restriction was in force between 8 am and 8 pm, and traffic was not restricted on Sundays. Public transportation service was increased during the restriction period.