By Mrinalika Roy and Seher Dareen

Jan 23 (Reuters) - Alcoa ( AA ) will likely send its

Australian output to the U.S. if the United States imposes

tariff on Canadian imports, the aluminum producer's CEO William

Oplinger said on Thursday.

U.S. President Donald Trump has threatened tariffs on

numerous countries including close allies such as Canada and

Mexico, and Oplinger's comments show how shipping flows could be

upended by such levies - adding potential costs to consumers

worldwide.

"We would be optimizing our global system based on any new

tariff structures ... there is a potential for metal to come out

of Australia and go into U.S. if there is a massive tariff

dislocation," Oplinger told Reuters.

The company produces 2.2 million metric tons of aluminum per

year, of which 900,000 metric tons are manufactured in Canada. A

majority of the Canadian output goes to the United States.

Earlier this week, Trump said he was thinking about imposing

25% duties on imports from Canada and Mexico on Feb. 1.

Alcoa ( AA ) would likely reroute its Canada-made aluminum to

Europe to avoid any potential tariff, Oplinger said.

"If there is 25% tariff on Canadian metal, and only 10% on

non-Canadian metal, that differential will attract metal into

the U.S. from the Middle East and India."

Any potential tariff will add about $1.5 billion to $2

billion in costs for aluminum consumers in the United States,

Oplinger said, adding that industries such as packaging and

automotive will likely see the most impact.

GREEN ALUMINUM DEMAND

Alcoa's ( AA ) biggest market for low-carbon aluminum remains

Europe, where the company ships nearly half of the material it

produces.

Using clean energy such as hydropower to make the metal

allows the producers to charge a premium as manufacturers using

green aluminum in their processes can generate more carbon

credits, which can be used to offset an entity's emissions.

Alcoa ( AA ) charges a 1% premium, coming up to between $20 and $40

per ton, since there is more supply than demand for low-carbon

aluminum.

"There is ample supply, but that supply is not growing ...

by the end of the decade you should see demand outstripping

supply, which should drive premiums higher for low-carbon

aluminum," Oplinger said.