Delhi along with 25 other Indian cities have higher air pollution levels than Beijing adn three Indian cities are as much polluted as Delhi, according to a WHO report.

This has been shown by a 2014-version of the Ambient Air Pollution (AAP) Database released by WHO few days ago.

The report added that only three of these 25 cities are now using the most advanced BS IV fuel emission norms in India and it is high time that the government comes up with new plans to curb vehicular pollution.

The AAP data has results of outdoor air pollution from almost 1,600 cities in 91 countries and finds that of the 20 cities with the worst air quality, 13 are in India.

The Indian Institute of Tropical Meteorology, which works under the Ministry of Earth Sciences, however, rejected the WHO findings. It is to be noted that the WHO results are based on data collected by the Central Pollution Board.

The institute stressed that the Delhi's pollution levels have been overestimated by the WHO and it has underestimated Beijing's level. The Delhi government also raised questions over the ambiguity in the data available to WHO on pollution in China.

The environmentalists, however, remarked that we need to admit that there was a problem at hand, especially with Dehradun, Pune and Jammu, which were thought to be cleaner cities, making it to the list of 20.

The WHO report said that the recorded levels of fine particulate matter (PM) with diameter of 2.5 micrometres or that are lower in these three cities than in Beijing.

Compared to Beijing's 56 microgram per cubic meter (ug/m3), the three above mentioned cities were found to have PM 2.5 concentrations of 77, 59 and 56 ug/m3, respectively.