FUZHOU, China/MELBOURNE - China's top copper smelters held an unscheduled meeting in Shanghai on Tuesday to reaffirm their position that there will be no shortage of copper concentrate supply in 2018 as the key contract renegotiation season hots up.

The 10 companies on the China Smelters Purchase Team (CSPT) met to conduct a "comprehensive and systematic analysis" of supply and demand dynamics after their return from the recent London Metal Exchange (LME) gathering, an official within the group told Reuters.

The move came in response to views expressed by miners at LME week, held in London from October 30 to November 3, that there will be a shortage of copper concentrate in 2018, said the official, who declined to be named.

A shortage of concentrate is negative for smelters as they have to compete for supplies by charging miners less to process the raw material into copper metal.

Copper prices have risen about 22% so far this year, partly driven by strong demand in China, the world's top copper consumer, providing good margins for miners.

The CSPT, however, which sets benchmark treatment and refining charges (TC/RCs) for copper concentrate processed in China, maintains that 2018 supply and demand will be "basically balanced, with a slight surplus," the official said, adding that a deficit "does not exist."

An ample supply of concentrate allows the CSPT to set higher charges. Its fourth-quarter benchmark TC/RCs, at $95 per tonne and 9.5 cents per pound, respectively, were above market expectations.

This contrasts with deals in the spot market, however, where fees charged by Chinese smelters have ranged from $80 to $90 a tonne and 8 to 9 cents a pound so far this quarter.

Three mining and trading sources told Reuters of two recent spot processing deals with Chinese smelters agreed for numbers in the mid-$50s, one by a major Chilean producer and another by a smaller Australian miner.

Mine supply is also vulnerable to disruption next year with around 40 contract renegotiation agreements due.

Members of the CSPT, which include Jiangxi Copper Co, Jinchuan Group and Tongling Nonferrous Metals Group, are expected to sit down for more talks with miners during Asia Copper Week in Shanghai from November 28 to December 1.

Even without taking into account the impact of China's environmental crackdown on smelters, "the market remains balanced", the CSPT official said, adding that the date of the group's next meeting had not yet been fixed.