Unlike some investment banks such as Goldman Sachs however, Antaike is less bullish on copper, predicting a 6.1% drop in average prices in the July to December period from year-to-date levels.

A base metals rally this year has contributed to talk of a commodities supercycle as demand roars back from the pandemic.

London Metal Exchange aluminium hit a three-year high of $2,603 a tonne last month, while copper surged to an all-time peak near $10,750.

Antaike sees LME aluminium averaging $2,450 in the second half, analyst Xia Cong said during a webinar. That is up 9% from a year-to-date average of $2,248 and above current levels of around $2,420.

Supply from top producer China has tightened amid curbs on power use by smelters in Yunnan and Inner Mongolia, Xia noted.

Antaike also raised its forecast for China's primary aluminium imports this year to 700,000 tonnes from 450,000 tonnes, although it maintains shipments will not match the bumper arrivals in 2020.

It expects tin to be the second-best performer, not far behind aluminium with an 8.8% gain in the second half as demand outstrips supply.

But Antaike believes that for copper, fundamentals do not support prices remaining near record highs.

An overseas demand recovery has already been priced in and it will be "difficult for actual demand for copper to further significantly increase" with the shift to service-based economies, Xia said.

Antaike kept its forecast for China's refined copper imports in 2021 unchanged at 3.4 million tonnes and expects copper scrap imports to rise by 400,000-500,000 tonnes this year.

It also sees nickel prices slumping 10.7% in the second half - making it Antaike's tip for the worst base metals performer - on fading expectations of a supply shortage.

(Reporting by Tom Daly and Mai Nguyen; Editing by Jan Harvey)