JLR said its UK factories were expected to remain closed until at least Wednesday after work was disrupted by a cyber attack just over a week ago.
They include plants in Solihull, Wolverhampton and Halewood.
The company shut down its IT systems in response to the attack on 31 August, in order to protect them from damage. However, this caused major disruption.
In a statement on Monday, it said: “We continue to work around the clock to restart our global applications in a controlled and safe manner following the recent cyber incident.
“We are working with third-party cyber-security specialists and alongside law enforcement.”
But Warwickshire-born Mr Palmer, who now runs green energy firm Palmer Energy Technology, said: “Car companies rely on continuous production and anything that interrupts production is a problem.”