Bilateral trade between China and Russia expanded quickly in the first four months of 2018, and the volume is expected to exceed $100 billion by the end of the year, a senior Chinese trade official said on Thursday.According to recent customs data, Sino-Russian trade grew 30 percent year-on-year to $31.2 billion between January and April."The Russian economy is steadily turning for the better and its market demand is rising, driving China's exports to the country up 21 percent on a yearly basis during the January to April period," Gao Feng, spokesperson for China's Ministry of Commerce (MOFCOM), told a press conference held in Beijing.The increase in imports of bulk commodities from Russia is another favorable factor, Gao said.From January to April, Russia's exports of crude oil through a pipeline running to China reached 12.4 million tons, an increase of 47 percent compared to the same period in 2017, and Russia has been China's largest supplier of crude oil in the past few months, Gao noted, citing data released by the Russian authorities.The two countries are beefing up efforts to foster new growth sectors supported by bilateral trade, Gao said, noting that Russian exports of agricultural products to the Chinese market increased by 35.5 percent year-on-year in the first quarter of 2018.The spokesperson also noted that bilateral investment in mega projects is aiding the expansion of trade between China and Russia.In recent years, China has been stepping up efforts to invest in Russia's energy, nuclear power, aerospace and infrastructure sectors, according to MOFCOM."Favorable factors that drive Sino-Russian trade growth are accumulating," Gao said.He added that bilateral trade between the two countries will see double-digit growth this year, with the volume expected to exceed $100 billion by the end of 2018.