CBI boss John Cridland said action by the UK outside plans already in place by the OECD would “be a concern for global businesses”, according to the BBC.
Osborne announced a 25% tax on profits generated in the UK but which companies attempt to divert overseas in the Autumn Statement on 3 November.
The Chancellor claims his crackdown will raise £1bn from multinationals.
Tax campaigners say tax reform to prevent international companies from paying low tax is hard, but possible.
John Cridland, CBI director-general, said: “International tax rules are in urgent need of updating, but the decision for the UK to go it alone, outside the OECD process, will be a concern for global businesses, and moving the goalposts on offsetting losses risks creating a worrying precedent.”