BERLIN (Reuters) - Volkswagen VOWG_p.DE sold a record 6.24 million of its VW-branded vehicles last year despite delivery problems caused by new anti-pollution rules, but warned the company would continue to face considerable challenges in 2019.

FILE PHOTO: Volkswagen Polo models are parked outside the company's plant in Pamplona, Spain October 30, 2018. REUTERS/Vincent West/File Photo

Still battling to recover from a 2015 emissions test cheating scandal and facing tighter European environmental rules, the German automaker has been trying to boost sales and cut costs to fund an ambitious shift to electric cars and automated driving.

At the same time, trade disputes with China driven by U.S. President Donald Trump’s ‘America First’ policies have caused uncertainty in the global auto industry.

“2019 will once again be a year of enormous challenges for the brand, aside from volume growth we will focus even more on our profitability,” Chief Operating Officer Ralf Brandstaetter said.

VW brand sales rose 0.2 percent last year thanks to growth in South America, the United States and Europe, compensating for a decline in China and difficulties registering cars following the introduction of Worldwide Harmonised Light Vehicle Test (WTLP) emissions standards.

The numbers do not include sales under the Audi, Porsche, Skoda, Bentley, Bugatti, Lamborghini and Seat brands, which are also owned by Volkswagen.

The VW brand increased market share in China in 2018 but its vehicle sales fell 2.1 percent with the world’s largest passenger car market on track for an annual sales contraction not seen since at least 1990.

For the wider Asia-Pacific region, sales dropped 1.7 percent.

“This decline is mainly due to developments in China, where consumer restraint continues in an uncertain macroeconomic environment,” the company said.

Despite rising 3.6 percent for the year, European sales took a hit after stricter anti-pollution rules were introduced in September.

“2018 was marked by significant uncertainty in some regions, especially in the second half,” VW brand sales chief Juergen Stackmann said in a statement, but he added that new products had helped offset that.

The company sold around 50,000 electric and hybrid cars, a 13 percent increase compared with 2017.