The state will move the Supreme Court (SC) against the high court stay on the order to phase out vehicles more than 20 years old from the city, transport minister Subhas Chakraborty said in the Assembly on Monday.

Replying to a question raised by Manas Bhuiyan (Congress), the minister said the state could not implement the order aimed at curbing pollution because of transport operators, who had gone to court and obtained a stay.

Chakraborty announced a government plan to build a 50-km elevated ring road that would start from Strand Road and pass through Strand Bank Road, Salt Lake, Prince Anwar Shah Road and Tollygunge Circular Road, before merging with Strand Road again.

“Experts are now working on a detailed project report. If everything goes well, work will start in September-October and end by 2010,” said the minister. A transport department official later said the Rs 3,000-crore project will be executed on a build-operate-transfer basis.

In a bid to curb the number of road mishaps, the minister said, the government is considering to stop the commission-based system of payment for drivers and conductors of private buses. A fixed salary will dissuade them from rash driving, he explained.

Back on pollution, the minister said the government is planning to build a number of truck terminals on the fringes to ensure that goods vehicles do not get to enter the city. Smaller, and less-polluting, vehicles will ferry the goods from the terminals to the city markets.

Chakraborty, however, pointed out that vehicles account for only 30 per cent of the city’s pollution. “There other causes as well, which we are trying to tackle,” he added.

Calcutta, the minister said, is the least polluted among the five metropolitan cities — the others being Delhi, Mumbai, Chennai and Bangalore.