BMW won't yet spill the beans on what its flagship SUV, to be called the X8, will embody, but new details on the vehicle have surfaced.

According to an Autocar report published Friday, the X8 will place its emphasis on rear-seat passengers and their comfort.

Additionally, it should feature a sloping roofline and more "coupe-like" design potentially like the smaller X4 and X6. The report claimed BMW will position the X8 flagship as a Range Rover rival, though it will also compete with the Bentley Bentayga and Rolls-Royce Cullinan with every option box checked off.

The new details follow BMW's move to trademark the X8 name in numerous markets around the world and most recently in Asia.

2018 BMW X6

2018 BMW X6

Previously, the X8 was thought to not go the coupe-SUV route. Instead, it was understood that BMW's goal would be to maximize rear-seat room, especially for Chinese consumers. However, the latest details from Autocar suggest designers and engineers will still emphasize extra space even with a sloping coupe-like roofline.

The German marque will likely achieve this by featuring just four or five seats. The upcoming BMW X7, which the X7 iPerformance concept previewed, will likely boast three rows of seats for seven seats total.

Packaging and the SUV's platform is proving difficult for BMW, though. The latest report reiterates the fact engineers will likely have to take elements of BMW's CLAR modular platform and the Rolls-Royce Cullinan's aluminum architecture to build the flagship SUV. By using both architectures, engineers will be able to achieve the rigidity needed without adding too much weight.

A final decision on what form the X8 will take is expected to be made later this year before the SUV surfaces around 2020.