Nearly 91,000 people from the new member states of the European Union registered to work in Britain in the first five months after EU expansion, official figures reveal.
Home secretary David Blunkett said the worker registration scheme – created because of concerns the UK would see huge numbers of migrants from Eastern Europe – had been a success.
Blunkett said the new arrivals had helped to fill job vacancies in hospitality and agriculture, and had also legalised some who had not previously been paying tax.
"Our commonsense approach to EU enlargement has put us at a clear advantage compared to the rest of Europe," he told a TUC conference on migrant working in central London.
"Illegal workers have legitimised their status and are contributing to the economy, benefiting from protection in the workplace and allowing us to focus resources on other forms of illegal working."