Earlier this year the carmaker said it would cut production because of Brexit uncertainty and changes to taxes on diesel cars - the United Kingdom has increased the Vehicle Excise Duty (VED) rate for diesel cars by one band in the first year.
Reports suggest that the Indian-owned manufacturer will confirm the announcement, as well as a drop in production for its Solihull and Castle Bromwich factories, on Monday. "Following a review of planned volumes, we are planning to make some temporary adjustments to the production schedule at Halewood in Q2". The company stressed it remains committed to its United Kingdom plants, having invested more than 4 billion pounds since 2010 to future-proof manufacturing technologies to deliver new models.
Latest employee figures say there are 3,200 people employed at the Castle Bromwich site and a further 10,000 at Solihull.
A source told new agency Reuters that 1,000 roles would be slashed as part of the moves.
In January, the firm said it would temporarily reduce production at its other British plant of Halewood later this year in response to weakening demand due to Brexit and tax hikes on diesel cars but did not detail any job losses. Solihull is home to the Jaguar XE, the Range Rover, the Land Rover Discovery, and the Range Rover Sport, and now employs more than 10,000 people.
"So in our home market, it's important that the economy can grow and that we have free opportunity to sell our cars".
The automaker saw a 26% drop in sales in the United Kingdom in the first three months of 2018 while sales in Germany fell 32%.
Julian Knight, MP for Solihull, said: "The news that has come to us is disturbing, and I am in regular contact with JLR on this issue".
The UK's biggest carmaker blamed the "continuing headwinds" affecting the vehicle industry for the move.