BENGALURU – Aluminium products maker Arconic Inc slashed its 2018 forecasts for profit and free cash flow on expectations that the price of the metal would remain high this year due to sanctions on Russian supplies and a 10% duty on aluminium imports.

Shares of the company, which makes aluminium products used in airplanes and trucks, fell 17.8% as the company also said high prices squeezed margins across its businesses in the first quarter.

Aluminium prices rose sharply in the first quarter than a year earlier as output fell in top producer China, where the government has shut down some aluminium capacity.

New York-based Arconic said it now expected full-year profit of $1.17 to $1.27 a share, down from its previous forecast of $1.45 to $1.55, and halved its free cash flow estimate to $250-million.

The updated forecast assumes current aluminium prices will hold at these elevated levels, Chief Financial Officer Kenneth Giacobbe said on a post-earnings call with analysts.

Seaport Global Securities analyst Josh Sullivan said for the company's upcoming long-term contracts - given its outlook on prices - it will have try to pass on price increases to customers.

President Donald Trump this month imposed sanctions on Rusal , Russia's biggest aluminium producer, and some other companies, in response to Moscow's alleged meddling in the 2016 U.S. election.

Rusal has been considering a range of measures to try to convince Washington to lift the sanctions, which have led customers to stop buying its aluminium.

Arconic said it had been in active talks with various US government departments on the process of sanction supply, adding that some of its operations depending on Rusal for their primary aluminium supply are functioning normally.

New York-based Arconic said operating income, excluding special items, fell 11.5% to $345-million.

However, Arconic raised its revenue forecast to $13.7-billion to $14-billion for the year, from its previous estimate of $13.4-billion to $13.7-billion.

Sales rose 7.9% to $3.45-billion in the first quarter from a year earlier, slightly above the average analyst estimate of $3.34-billion, with aluminium prices accounting for $109 million or about 40% of the increase.

Excluding one-time items, Arconic earned 34 cents per share, also edging past analysts' average estimate of 33 cents, according to Thomson Reuters I/B/E/S.