Japan has again advised importers not to import Chinese frozen spinach, claiming it has found two batches from China with a higher pesticide residue than Tokyo permits.

The Chinese State General Administration for Quality Supervision and Inspection and Quarantine said it is negotiating with the Japanese Government to see what can be worked out.

The Ministry of Commerce expressed concern but refrained from making further comment while the two sides are continuing their bilateral talks.

On Tuesday last week, the Japanese Government renewed an advisory safety notice to importers on the purchase of Chinese frozen spinach.

Japanese media reported that a random sample of two Shandong-based companies' spinach exports to Japan found higher pesticide residues than Japan permits.

At the end of June last year, Japan advised firms not to import Chinese frozen spinach but it took back that advice at the end of February. It then announced that imports of Chinese frozen spinach could resume provided they passed Japanese entry inspections and had a health certificate from Chinese quality inspection and quarantine administration.

This put an end to an eight-month Japanese block on Chinese frozen spinach.

But Chinese exporters remained cautious. They complained that Japan's "unnecessarily strict" entry inspection was a "green trade barrier" against Chinese frozen spinach.

Huang Nanfu, general manager of the Taitai Xingye Food Co Ltd in Changshu in East China's Jiangsu Province, said: "The Japanese Government still inspects each batch of Chinese frozen spinach imports. It costs more and takes longer for our goods to get to the Japanese market than in 2001."

Before the latest ban, each entry inspection cost 254,500 yen (US$2,170) and it takes about a month for Chinese frozen spinach to reach the shelves of Japanese shops.

Although the cost was down from 592,000 yen (US$5,050) in March, when the entry inspection standard was stricter, the entry inspection measures were still rigorous because the Japanese Government inspected 100 per cent of the goods. It sampled only 10 per cent before last year.