Referring to the situation in Delhi, which is witnessing alarming levels of AQI, the HC asked what effective measures can be taken to address the issue.

"We are all seeing what is happening in Delhi. What is the effect of that?" the bench questioned, posting the matter for hearing on Friday.

Hayli Gubbi, a shield volcano in Ethiopia's Afar region, erupted on Sunday, producing a large ash plume that rose to around 14 km in the sky.

The plume spread eastward across the Red Sea and towards the Arabian Peninsula and the Indian subcontinent.

Shiv Sena MP Milind Deora wrote to the BMC Commissioner Bhushan Gagrani, urging him to take immediate and extraordinary action, including a temporary halt to all digging and construction sites until the air quality improves.

"Mumbai's air pollution crisis is no longer a seasonal issue --- it is a public health emergency. India needs a nationwide war and a national consensus against air pollution," Deora said.

Shiv Sena (UBT) leader Aaditya Thackeray said even as Mumbai's AQI worsens every day, and the city competes with Delhi on this score, the governments from top to bottom, currently controlled by the BJP and its allies, conveniently ignore people's plight.

"In Mumbai, builders and contractors are a priority for the BJP government, while apart from the construction and demolition works, tree felling in the name of development is the new mantra of the BJP," he alleged.

On its part, the civic body pointed out that various steps are being undertaken to address air pollution, including forcing bakeries and crematoriums to use cleaner fuels, introducing electric buses, managing construction debris scientifically, and using machines to sprinkle water on roads to control dust.

In October last year, the BMC issued 28 guidelines which include installing metal fencing and green cloth covering around construction sites to control dust, carrying out water sprinkling, properly storing and transporting debris, installing air quality monitoring devices and setting up smoke absorption systems, among other measures.

To ensure compliance, flying squads have been formed, the civic body said.