HARBIN -- Customs authorities in Heilongjiang, China's most northeastern province as well as one that borders Russia, said Tuesday that the province's trade with Russia reached $8.96 billion in the first five months of this year, up 30.8 percent from a year earlier.

Trade with Russia accounted for more than 60 percent of the province's total foreign trade volume in the same period, the provincial customs department said in a statement.

Heilongjiang's foreign trade volume stood at $14.8 billion in the first five months, up 6.6 percent year-on-year. Exports dropped 30.8 percent year-on-year to $4.46 billion, while imports increased 39 percent to $10.36 billion, the statement said.

According to the statement, the shrinking global market and fewer overseas orders were responsible for the decrease in exports.

Meanwhile, the province noticeably increased imports of natural resources in the same period. For instance, it imported $7.74 billion worth of crude oil in the first five months, up nearly 60 percent year-on-year.

Saudi Arabia surpassed the United States to become the province's second-largest trading partner. Trade with the Middle East country stood at $940 million in the January-May period, showing a more than seven-fold increase from the same period last year, according to the statement.