With the manufacturing facility set to start later this year and the company has already announced that it is set to move all production of its Discovery vehicle to Slovakia before building its new Range Rover at an English factory.
JLR have said the decision to move production and the "potential" job losses was a "tough" decision to make.
Jaguar Land Rover first announced its intention to begin production of the Discovery in Slovakia in 2016, but did not mention at the time that the process could involve the migration of the model's entire UK-based production line.
In April, JLR announced a temporary cut in production and job losses at its Solihull and Castle Bromwich plants, pointing to "continuing headwinds" facing the auto industry.
Two years ago the firm, owned by India's Tata Motors, insisted that its new Slovakia plant would "complement" its United Kingdom operations, with the Discovery built in both locations.
After its makeover, the plant will produce the new Range Rover and Range Rover Sport models.
JLR has previously said its next-generation Discovery will be built at its Slovakia plant and on Monday announced there could be some job cuts in Britain as a result.
The Land Rover Discovery - in many ways, the heartland of the brand - will no longer be made in the UK. It has also blamed Brexit for hitting demand in Europe's second-largest autos market, where demand fell 6 percent a year ago.
JLR said the switch of production to the £1bn plant in Nitra, Slovakia - which is due to open at the end of the year - is not connected to concerns over Brexit.
"This significant investment and technology upgrade in Solihull in order to accommodate our next-generation of flagship Land Rover models, and the refit of our Halewood plant for the next Evoque, is proof that we remain committed both to the United Kingdom and to transformation and growth", the company said.
Alongside the Slovakia announcement, Jaguar said it will invest millions in a revamp of Solihull, where the new Range Rover and Range Rover Sport models will be built. The biggest plant in the company, it now employs 9,000 people. Sales for the Jaguar E-PACE also continue to ramp up and we look forward to retails of this exciting sporty compact SUV beginning in China in August.