German carmaker BMW Group has said it expects to spend its largest annual sum ever on research and development (R&D) during 2018.

The firm, which manufactures and sells BMW, Rolls-Royce and Mini-branded cars, is set to splurge as much as 7 billion euros ($8.6 billion) this year as it ramps up its presence in electric and autonomous vehicles.

In its annual report, released Wednesday, the BMW Group said the R&D ratio would sit between 6.5 and 7 percent of sales in 2018, above the usual range of 5 to 5.5 percent.

BMW Group chairman Harald Kruger told investors in a speech that the company was in the midst of a busy period as it prepared to release 20 new car models this year.

"The biggest model offensive in our history is currently in full swing. We are now in phase two. We will be releasing another 20 new and revised models this year," he said.

BMW Group said it expected group pre-tax profit to surpass 10 billion euros for 2018.