Chinese workers are working "round the clock" to finish a temporary dam project to reduce the impact of a river-born chemical spill on the Russian city of Khabarovsk, a Foreign Ministry official said yesterday.

"Chinese workers are braving the cold to insure the dam is built as soon as possible," said Foreign Ministry spokesman Qin Gang at a regular news briefing.

The construction of the dam began on Friday on the Fuyuan waterway off the Heilong River, and it is hoped it will channel the slick away from the water pumps in the Russian border city.

"China stands ready to work with Russia to minimize the impact of the pollution," Qin said.

Daytime high temperatures in the area this week have been about -15 C.

The pollution spill in Northeast China's Songhua River was caused by an explosion at a chemical plant in November.

It is estimated that about 100 tons of benzene and nitrobenzene fell into the Songhua River after the accident.

The 180-kilometre-long toxic slick entered the Amur River from China's Songhua River on December 15.

The Songhua River flows into the Heilong River, which merges with the Wusuli River in the Russian border city to become the Amur.

Qin said the temporary dam will be removed after the pollutant slick passes Khabarovsk.

"China is paying to build and demolish it," Qin added, giving no further details about how much the project will cost.

The cross-border water pollution has drawn serious concern from Chinese leaders, including President Hu Jintao and Premier Wen Jiabao.

"China adopts a responsible attitude towards environment protection and has taken immediate measures to minimize the impact of the pollution on Russia's Far East regions," Qin said.

Russian Ambassador to China Sergei Razov yesterday welcomed China's efforts to check the Songhua River water pollution, saying it was a common challenge faced by the two sides that requires joint efforts to minimize the damage.

Source: China Daily