BERLIN (Reuters) - Valuation changes to vehicles in transit as a result of U.S. President Donald Trump's tariffs policies were among the factors weighing heavily on Volkswagen's operating results in the first quarter, which fell to 2.8 billion euros from 4.6 billion last year.

Results came in far short of market expectations of around 4 billion euros.

The company confirmed its full-year outlook of up to 5% sales growth and operating return on sales of between 5.5% and 5.6% but said these forecasts excluded the possible impact of tariffs since it was too early to assess their impact.

Adjustments to provisions for the diesel issue and the valuation of vehicles in transit in connection with U.S. tariffs took 300 million euros from the operating result. Provisions for Europe's carbon regulations cost 600 million euros and restructuring of VW's software unit cost another 200 million euros.

Groups sales rose around 3% to 78 billion euros.