Britain on Tuesday closed the door on most Romanian and Bulgarian workers for at least another year, as the government battled to restore confidence in an increasingly shambolic immigration policy.

As Liam Byrne, immigration minister, announced he would keep tight controls on migrant workers from the two Balkan countries until at least the end of 2008, ministers conceded there were 300,000 more foreign workers in the UK than official figures had suggested. And confusion deepened further as senior MPs claimed the true total could top 1.5m.