The Audi logo is shown at the North America n International Auto Show in Detroit, Michigan January 14, 2013. [Photo/Agencies]

Germany's Audi will grow spending on new models, plants and technology in coming years as the luxury carmaker steps up efforts to catch larger competito r BMW, people familiar with the matter said.

The Volkswagen-owned division plans to spend more than 20 billion eu ros ($27.46 billion) on global operations through 2018, said the people on condition they not be identified because Audi's spending plan won't be published until December 27.

That equates to over 4 billion euros a year, compared with 2.6 billion in the carmaker's budget of December 2011.

German magazine Auto Motor und Sport reported the size of Audi's investments on Dec 12, citing chief executive Rupert Stadler. Ingolstadt-based Audi declined to comment.

Planned investments will sustain Audi's foreign expansion as the carmaker sets up factories in Mexico and China and eyes production in Brazil. Audi plans next year for the first time to build more cars outside Germany than within the country.

Audi aims to sell at least 2 million cars a year and overtake luxury-sales champion BMW by the end of the decade. The brand's expansion is part of VW's goal to overtake Toyota and General Motors as the world's No 1 automaker no later than 2018.

Higher spending at Audi follows an announcement by VW last month to shield vehicle-based investment from cuts in other areas, responding to sluggish auto demand.