Prototype of BMW's upcoming 4-Series undergoing tests

This is the first time we’ve spotted the new BMW coupe version of the recently unveiled 3-Series. Rumoured to be taking a new 4-Series moniker, it’s the first of several derivatives of the 3-Series platform due in the next few years. A GT version, similar in looks to the current 5-Series derivative, is also pencilled in for launch, along with the expected Touring estate version and a range-topping M3.

The upcoming model takes several design cues from the 6-Series

On this 4-Series prototype, we can make out the shape of the upcoming two-door coupe which should be larger than the new 3-Series and taking several design cues from the 6-series coupe.

Speculation is that the new 4-series will feature both two-door and four-door sport coupe variants (as BMW will be doing with the 6-series as well), to compete against the likes of the Audi A5 range, and there may also be a cabriolet version too.