Members of the media photograph a prototype iMac Pro during the annual Apple Worldwide Developer Conference (WWDC) in San Jose, California, U.S. June 5, 2017 / REUTERS/Stephen Lam

Apple has just launched the new iMac Pro, the most powerful Mac the company has ever made.

The company says it's as fast as a full workstation but inside a Mac. 

It looks the same as the iMac but comes in the dramatic dark grey finish on the MacBook Pro and other new Apple devices.

The all-in-one comes loaded with a 27-inch Retina 5K display, an AMD Radeon Vega GPU and an 8-, 10- or even an 18-core Xeon processor and up to 22 Teraflops of graphics computation, for monstrous performance.

iMac Pro also supports up to 4TB of SSD and up to 128GB of ECC memory, and with four Thunderbolt 3 ports can connect to up to two high-performance RAID arrays and two 5K displays at the same time.

“We’re thrilled to give developers and customers a sneak peek at iMac Pro," said John Ternus, Apple’s vice president of hardware engineering.

"This will be our fastest and most powerful Mac ever, which brings workstation-class computing to iMac for the first time.

“We re-engineered the whole system and designed an entirely new thermal architecture to pack extraordinary performance into the elegant, quiet iMac enclosure our customers love — iMac Pro is a huge step forward and there’s never been anything like it.”

The iMac Pro is coming out in December, and will cost £4,999.