The court told Uber: "You keep on your payroll someone who took 14,000 documents and is liable to use them."

"What prevented him from bringing a laptop to work every day and consulting the files?" said Judge William Alsup, according to Reuters.

Uber says its technology is different to that used at Google and maintains that it does not have any of the allegedly stolen files on its systems.

The court banned Mr Levandowski from working on Uber's self-driving car technology earlier this month as proceedings began.

In its termination letter, Uber said Mr Levandowski "impeded Uber's internal investigation and defence of the lawsuit". It added that his refusal to help gives it grounds to allege that he did not "return or destroy all property and confidential information belonging to any prior employer" when he joined the business.