China was Japan's biggest trading partner in both exports and imports in the January to June period of this year, with exports to China surpassing those to the United States for the first time ever, the Japan External Trade Organization said Wednesday.

Although exports to China fell 25.3 percent from a year earlier to $46.5 billion and imports from the country dropped 17.8 percent to $56.2 billion, trading with other countries and regions, including the United States, showed larger declines, JETRO said in its report.

While the total value of the two-way trade in the half-year period with China slid 21.4 percent, the trade with China accounted for 20.4 percent of the total, while that with the United States accounted for 13.7 percent and that with South Korea 6.1 percent.

The data were calculated by JETRO based on yen-denominated trade figures released by the Finance Ministry.

But JETRO said Japan's trade with China is almost certain to contract in 2009 for the first time since 1998, when bilateral trade was affected by the Asian currency crisis.

In order for Japan-China trade to see a recovery, it is necessary that advanced nations' economies recover and give China greater external demand, a JETRO official said.