More than a third of women and a quarter of men said they wanted to stay, many of whom had changed their minds since arriving in the UK.

The Joseph Rowntree Foundation's report also found that one in four migrants spends no time with British people.

The study, based on interviews in 2002 and after EU enlargement in May 2004, draws on experiences of 600 migrants.

Construction workers, farm labourers and au pairs were among those interviewed about their lifestyles.

'Treated as equals’

Researchers spoke to working migrants from Poland, Slovakia, the Czech Republic, Lithuania, Ukraine and Bulgaria.

They found 6 percent of those surveyed in October 2002 said they would stay in the UK when they first arrived.

Eighteen months later, of those who remained in the UK, just under a quarter said they would stay permanently.

By the end of 2004, 29 percent of Eastern European migrants said they would stay "for good".

Factors in making a decision included their legal status, income, gender, where their dependents lived, having friends in the UK, and how they were treated, the report said.

Questioned about their experiences in Britain, two-thirds of the sample did not know how to register with a doctor.

Almost half of the migrants had received no information about conditions attached to their immigration status.

Four out of 10 said Britons treated them as equals, but three out of 10 said they did not.

Just one-third had taken English classes and many felt they had only limited contact with British people.

A waitress from the Ukraine said they “do not let you into their circles”.

Facing challenges

BBC home editor Mark Easton said that, while the study provided a glimpse into the world of migrant workers in the UK, it did not show the true picture as there were no figures showing how many go home.

However, it did highlight the need for the government to look at service provision, integration and learning English, he said.

The foundation's director, Julia Unwin, said the research showed that the government should value migrants as "more than simply an economic resource".

She said ministers "must continue to place importance on ensuring their integration into wider British society, even when their stay is expected to be temporary".

A spokesman for the communities department said he recognised that "both new migrants and more settled communities can face challenges when migration patterns change".

He said a report by the Commission on Integration and Cohesion next month would put forward "practical proposals to encourage better integration".

The commission would encourage measures including employers providing English lessons for their staff, he said.

But the director of research group Civitas, David Green, said some people in the UK were finding it hard to compete with these newcomers.