The Swiss-Italian is a former member of the Ferrari Driver Academy and was a Sauber Formula 1 test and reserve driver in 2015.
He won the FIA Formula 3 European Championship in 2013 with Prema and spent three seasons in GP2 before switching to GT racing in 2017, joining the Mercedes-AMG driver roster a year later.
Title success followed in the 2018 Blancpain GT Series Sprint Cup with AKKA ASP Team and the 2019 FIA GT World Cup with Team GruppeM Racing.
As well as championship success in ADAC GT Masters and GT World Challenge Europe Cup, the 28-year-old also won the Spa 24 Hours last term alongside Daniel Juncadella and fellow British GT driver Jules Gounon.
“I’m really happy to be adding the British GT Championship with RAM Racing to my plans for the season,” he said.
“The British tracks are world-famous and look amazing, so I can’t wait to get to drive them and learn some new ones. Plus, I really love racing in the rain, which means the British weather won’t even be a problem for me!
“This year the level in British GT looks to be very high with a lot of professional drivers involved so it will be a nice challenge.
“I’m sure that between myself, John and RAM Racing we will have the tools to do a good job and fight for some nice results. I know we can have a very strong year.”
RAM will scale back to a one-car operation this year, with founder Dan Shufflebottom having left the team despite it winning the GT3 drivers’ title with Ian Loggie and the teams’ championship in 2022.
Ferguson returns with the squad's Mercedes-AMG GT3 after taking victory alongside Ulysse De Pauw at Snetterton last term, having previously raced in the GT4 class in 2021.
“I wanted to do something dramatic for British GT this year, and this is the culmination of many months of trying to get Raffaele onboard for this year, and I’m delighted,” said Ferguson.
“In my mind, I’ve got the best GT3 driver in the world in my corner, and his record speaks for itself. I know I’ll learn huge amounts from working with Lello this year, which will help me improve as a driver.”
The British GT media day takes place at Donington Park tomorrow (Tuesday), with the opening round commencing at Oulton Park on 10 April.