Nine large copper producers in China have agreed on an initial plan to cut refined metal output by more than 200,000 tons in 2016, which would be about 5 percent less than this year's level, an executive at one of the producers said on Saturday.

The agreement followed a producers' meeting on Saturday in Shanghai to discuss coordinated output cuts to support the market after prices in Shanghai and on the London Metal Exchange plunged to their lowest in more than six years.

China is the top refined copper producer and consumer in the world, but its slowing economy is adding pressure on the global market.

The nine producers also will ask the State-controlled industry body, the China Nonferrous Metals Industry Association (CNIA), to request the central government to investigate high-speed trading and malicious short-selling of copper contracts traded on the Shanghai Futures Exchange, the executive said.

The producers also agreed that the companies would consider bigger output cuts and finalize the amounts in the coming week, said the executive.

He was speaking on condition of anonymity but on behalf of the China Smelters Purchase Team (CSPT) group.

Chinese growth dipped to 6.9 percent in the third quarter, the weakest since the global financial crisis.

Zinc smelters and nickel smelters also called for production cuts earlier last week. Sources said on Friday China's State Reserve Bureau was considering buying more than 1 million tons of aluminum from local smelters, an initial sign that the government could agree to the first major bailout in its embattled metals industry since 2009.

The nine copper producers involved in the planned cut are members of the CSPT and include Jiangxi Copper Co and Tongling Nonferrous Metals Group.

These companies' production accounted for about 60 percent of the country's refined copper production in the first 10 months of this year.

"We're prepared to cut production by at least 200,000 tons," the executive told Reuters, adding that the cut could be expanded if copper prices fell further.

The companies will produce about 4.5 million tons of refined copper in 2015, he added.

The proposed cut is equal to about one-third of China's production in October.

The producers would mainly cut output that uses scrap as feedstock, the executive said.

The firms also use copper concentrates as feedstock.

"We are very serious about cutting production. We will have a meeting every two weeks to follow up proposed cuts by each company," he said.

The copper smelters, whose production is mostly registered for the delivery of the copper contract in Shanghai, would restrict sales of their metal to players that hold massive short positions, the executive also said.

CNIA, supported by some large metals producers, has already called for a short-selling probe on metals futures, sources said earlier last week.

Reuters