The team, which prepares and runs the factory Qatar M-Sport Ford Fiesta RS WRCs, began testing the R5 car in January and has already taken 18 deposits. Six of those cars are nearing completion at M-Sport.
M-Sport managing director Malcolm Wilson said at the launch: "I'm very, very excited about this car.
"This is the latest in a long line of great rally cars which have come out of M-Sport and, having driven this car myself last week, I have no doubting this car's capability.
"The R5 class is going to be extremely competitive and to be the first in the world to have our car ready gives me immense pride."
The FIA's technical delegates were in Cockermouth for three days last week, checking the legality of the all-new Fiesta, and the car is expected to be rubber-stamped for July 1.
Elfyn Evans will give the Fiesta R5 its competitive debut at World Rally Championship level on Rally Finland next month.
Before then, Thierry Neuville will drive one at competitive speeds on the Ypres Rally -although the Belgian classic finishes on June 30. Had the event run a day later, M-Sport would have been able to enter the car on the ERC counter.
The R5 class is for four-wheel drive, 1600cc turbocharged rally cars using more standard parts. The cars have been cost-capped at £160,000.
Peugeot, Citroen and Skoda are all working on their own R5 cars at the moment. Peugeot's 208 T16 is expected to be the next car to be unveiled.