An Indian court Monday suspended its ban on diesel vehicles more than 10 years old after New Delhi authorities complained they were struggling to comply with the order in the world's most polluted capital.

The National Green Tribunal last week announced a slew of measures to try to curb air pollution in Delhi including ordering older vehicles off the roads and cracking down on illegal construction projects in the capital and surrounding satellite towns.

Citing diesel vehicles as a major source of Delhi's toxic haze, the country's environment court ordered the city government to implement the ban within 20 hours.

But lawyers for the Delhi government appealed to the tribunal for more time, saying essential services such as garbage collection by mostly older trucks have been thrown into disarray.

"The court agreed and stayed its order for two weeks. No vehicles will be impounded during this period," Zubeida Begum, lawyer for the government, told AFP.

"Transportation of eatables to the capital has been hit hard, so has the garbage collection," she said.

Thousands of commercial trucks travel through Delhi every night, many of them on their way from one state to another because of a lack of bypasses on India's dilapidated highways.

According to local media reports, some 40,000 diesel cars have been effected by the court's ban in the capital and more than 90,000 in adjoining towns.

Prime Minister Narendra Modi earlier this month launched a new index to monitor air quality levels in Delhi but environmentalists criticised a lack of initiatives to curb the pollution.

The government is under intense pressure to act after the World Health Organization last year declared New Delhi the world's most polluted capital.

At least 3,000 people die prematurely every year in the city because of air pollution, according to a joint study by Boston-based Health Effects Institute and Delhi's Energy Resources Institute.

On Monday, the tribunal said the ban would be suspended until May 1 while it sought submissions from authorities on ways to ensure the ban was implemented effectively.

In November, the tribunal also ordered all petrol vehicles older than 15 years to be taken off the capital's roads in a bid to lower toxic air levels.