TOKYO - Japanese Minister of Economy, Trade and Industry Yukio Edano called on China Friday to abide by international trade rules after reported customs problems amid diplomatic tensions between the two neighbors, Kyodo reported.

Edano said at a press conference that the government is gathering information and has heard "various" things, but did not elaborate.

"We will act appropriately depending on the situation," he added.

Meanwhile, Finance Minister Jun Azumi told a separate press conference he is "paying close attention" to the reported problem with China, Japan's largest trading partner.

Their remarks came after media reports that Chinese customs authorities have tightened the inspection of Japanese products bound for China and Chinese goods bound for Japan in cities such as Shanghai.

In recent days, local media widely reported that the Chinese side is trying to hurt Japan economically for leverage in a bitter territorial dispute over a chain of islands in the East China Sea and "nationalization" plan introduced by the Japanese government.

The Japan Airlines announced the same day that it will cut back flights to China due to declining number of passengers.