Security giant Group 4 Securicor has refused to rule out electronically tagging its UK employees, despite the threat of industrial action by the GMB union.
The union claims the company's US division was planning to embed tracking chips in uniforms issued to security staff. It has since written to the firm's UK management to seek assurances that no similar plans exist for its 33,200 UK workers.
Paul Kenny, GMB acting general secretary, said: "There will be 'jackets off' protests across the UK security industry if these spy chips are used to tag workers.
"We want the company to give us a categorical undertaking that it will not use this technology to tag its UK workforce."
A Group 4 Securicor spokeswoman told Personnel Today the company had no plans to introduce electronic tagging "for the foreseeable future".
Kenny called for an informed public debate about the associated privacy issues.