With worsening air quality, particularly that of cities like Delhi, continuing to be a priority issue, the Centre has begun consultations with the governments of Delhi, Rajasthan, Haryana, and Uttar Pradesh.

"It is not just Delhi, the NCR includes parts of Rajasthan, Uttar Pradesh and Haryana. Also, some of the pollution in Delhi is from activities in these states. So we are adopting an air-shed management approach, just like we do watershed management for rivers," Environment Minister Prakash Javadekar said on Tuesday.

As a first step, the environment ministry has said that over the next 15 days it will put in place norms that will cut down on pollution generated by construction activities. Construction activities generate dust, or in air pollution parlance, particulate matter, which are of miniscule size but are most harmful to human health.

The environment ministry has already held a series of discussions with the Delhi state government to deal with the city's worsening air quality. However, since the National Capital Region is spread over four states—Delhi, Rajasthan, Haryana, and Uttar Pradesh—the ministry increased the ambit of the consultations.

Javadekar and officials from his ministry had held a meeting with the ministers and officials of the four states on Monday to chalk out a plan. The group will meet again on Monday, April 13, along with representatives of the Delhi Municipal Corporation and Delhi Police to draw up a time-bound plan, including a charter for immediate action.

"We held meetings with the environment ministers of Delhi, Uttar Pradesh, Haryana and Rajasthan yesterday and discussed the issue in detail. We have decided to meet on April 13 again where officials of municipal corporations and Delhi police will also be called. We have taken the first step. Construction waste is a big challenge as most of the dust through it including PM2.5 and PM10. We will frame the rules in 15 days, which will be posted on the website. Suggestions from public will also be invited before implementing them within two months," Javadekar said.

The minister said that the consultations would lead to a "concrete time-bound plan".

On Monday, Javadekar announced that the ministry was working on a war footing to formulate a plan and rules to address dust generated by construction. He said that if the dust is properly managed in the construction of Metro, why couldn't it be managed in constructions going across the city.

The minister warned that no one step was enough to tackle pollution, and that the effort to keep pollution under check had to be a continuous effort. "It is a daily fight. We can't sit back after taking a major step. We have always sat back. It is a war which we have to fight every day. It's an air-shed treatment by taking everybody. Yesterday, we all (ministers) met and decided to come out with concrete plans. Let us build up that action," he said.

Stressing that addressing air pollution required taking action on multiple fronts and by all stakeholders, Javadekar said that earlier in an effort to curb pollution, all industries were relocated outside Delhi, but that did not improve matters for long.

Next, he said, the Supreme Court ordered the use of CNG, but even that did not resolve the problem as the number of people and vehicles increased. "People talked about public transport so we thought of Metro. Twenty-seven lakh people travel in Metro but pollution persists as vehicle numbers and many other factors are growing," Javadekar said, adding that citizens can do many things to contribute to reduce pollution, such as observing lane discipline, avoiding congested roads, vehicle maintenance and avoiding idling engines at long stops. "All state governments, municipal agencies, traffic police and industries need to act together," he said.