EC AGREES REDUCTION OF DIESEL EXHAUST EMISSIONS The European Community (EC) agreed tough new rules to cut diesel exhaust emissions from trucks and buses in an attempt to reduce air pollution threatening vast stretches of the region's forests. Diplomats said EC environment ministers meeting here agreed member states would have to reduce by 20 pct over the next few years the emission of nitrogen oxide, widely seen as the main source of acid rain endangering forests and lakes. The reduction would be compulsory for heavy vehicles, with tougher standards imposed for new models from April 1988 and for all new vehicles from October 1990. The EC's executive Commission says the emission level of nitrogen oxide was expected to drop to 2.4 mln tonnes a year from three mln tonnes within the 12-nation Community if all heavy vehicles applied to the new standards. There are an estimated nine mln lorries and buses in use in the EC, according to Commission figures. The ministers also gave West Germany a go-ahead to move towards a ban on the sale of leaded regular petrol, after Bonn requested permission to do so to encourage the use of low-pollution cars, diplomats said. West Germany will still need ministers' final approval for such a plan. Diplomats said this was expected when EC environment ministers meet next on May 21. But the ministers added that the go-ahead for West Germany did not mean there would automatically follow a Community-wide ban on the sale of regular leaded petrol. Bonn intends to keep leaded premium petrol pumps, diplomats said. They added that, of the 97 mln cars in the EC, only 20 mln now ran on regular leaded petrol and these would risk no damage if they switched over to premium leaded petrol. Under EC law, ministers have to give member states special permission if they wish to be exempt from Community competition laws. This would be the case if West Germany were to implement a ban on the sale of leaded regular petrol.