The home secretary’s party conference speech proposing that companies compile lists of foreign workers has been declared a “hate incident” by police under crime recording policies that she has supported.

Amber Rudd’s remarks about tougher rules for immigrant workers and foreign students attracted fierce criticism at the Conservative party conference in Birmingham last October.

She said that the government would be “examining whether we should tighten the test companies have to take before recruiting from abroad” and ensuring that foreign workers were “not taking jobs British people could do”.

Joshua Silver, a physics professor at the University of Oxford, was so concerned that he reported the speech to police.

“I felt politicians have been using hate speech to turn Britons against foreigners, and I thought