Feb 14 (Reuters) - Canadian auto parts maker Magna International MG.TO cut its 2026 sales estimate while offering a weak revenue forecast for the current year on Friday and said challenges such as uncertain government policies have made forecasting "more difficult".

U.S.-listed shares of Magna were down 4.1% before the bell.

The company now expects its 2026 revenue to be between $40.5 billion and $42.6 billion, compared to a forecast of $48.8 billion to $51.2 billion it offered around the same time last year.

Aurora, Ontario-based Magna produces vehicle components and assembles cars at its manufacturing facilities for several top automakers, including BMW BMWG.DE, Mazda 7261.T and Ferrari RACE.MI.

U.S. President Donald Trump suspended his threat of steep tariffs on Mexico and Canada earlier this month, agreeing to a 30-day pause in return for some concessions.

But the threat has increased investor focus on results of Canadian companies such as Magna and Bombardier BBDb.TO, with the latter recently delaying offering a 2025 forecast, citing tariff-related uncertainty.

The tariff threat has intensified headaches for the Western auto industry, which is already grappling with rising competition from Chinese automakers and an inflation-hit consumer.

Challenges including light vehicle production volatility and "uncertain government policies" have made forward-forecasting more difficult, Magna said on Friday.

Its 2025 and 2026 forecasts do not incorporate any potential impact from the imposition of tariffs or changes in tariff rates, it said.

The company expects current-year sales to be between $38.6 billion and $40.2 billion, compared with average analysts' expectation of $42.41 billion, according to data compiled by LSEG.

Magna blamed a strong U.S. dollar, lower light-vehicle production by its customers and the end of Jaguar assembly production programs for the weak forecast.

Its fourth-quarter sales rose 2% to $10.63 billion, beating expectations of $10.30 billion. Adjusted earnings per share of $1.69 was above the estimate of $1.53 per share.

(Reporting by Nathan Gomes in Bengaluru; Editing by Pooja Desai)

((Nathan.Gomes@thomsonreuters.com;))