China, the world's top emitter of sulphur dioxide, has managed to cut emissions of the acid-rain causing pollutant in first half of 2007, but the government said on Tuesday that meeting national targets would be tough.

China has promised to cut emissions of major pollutants by 10 percent between 2006 and 2010, but last year the country failed to meet the annual target.

Emissions of sulphur dioxide in the first six months of 2007 reached about 12.6 million tonnes, down 0.88 percent from the same period last year, a report issued by the State Environmental Protection Administration (SEPA) said.

The progress could be attributed to efforts made by the electronic and power industries, it quoted a senior official as saying. China has offered slightly higher tariffs to power stations with desulphurisation equipment to encourage generators to strip it from emissions.

While power capacity increased by 18.3 percent, the sulphur dioxide emission dropped by 5.2 percent, which offsets the emission from other industries, the official was quoted as saying in a report on SEPA's Web site (www.sepa.gov.cn).

Although we have made some progress, the situation of cutting emissions remains grim.

COD, or chemical oxygen demand, a measure of water pollution, was up 0.24 percent compared to the same period last year, according to the research conducted by SEPA, the National Development and Reform Commission and the National Statistics Bureau.

Despite the central government's efforts to curb pollution from factories, mines and industrial plants that have driven frantic growth, local officials often prioritize economic development over environmental protection.

But the SEPA notice repeated central government policy that progress in reducing emissions would now be taken into account as a factor in the promotion and appraisal of local officials.

Many analysts expected China to overtake the United States this year as world's biggest emitter of greenhouse gases. But China rejects concrete caps on its emissions of most gases, saying development must be its top priority.