The US agency in charge of implementing new clean air legislation has moved to reassure the oil industry over new diesel regulations.

The Environmental Protection Agency said that the industry should not have a problem meeting new sulphur emission targets for diesel that came into effect this week.

"The agency expects a smooth transition and will closely monitor the industry as it transitions," the EPA said.

It added that achieving the "historic milestone" would "benefit Americans' health and the environment".

In order to meet the regulations, sulfur levels in diesel will have to see a 97 per cent reduction, from an average 500 parts per million to just 15.

When they have been fully implemented, the measures should result in the annual reduction of 2.6 million tons of nitrogen oxides and 110,000 tons of particulate matter.

Diesel meeting the standards will have to be sold at petrol stations by mid-October as trucks and buses that use clean diesel technology become available.

A further landmark will come in 2009, when both petrol and diesel-powered cars, pickups and SUVs will have to meet the clean air regulations.

Ÿ Adfero Ltd