Home Secretary Alan Johnson last night refused point blank to cap the number of immigrants coming to Britain.
And he said he does not 'lie awake at night' worrying about the population hitting 70million.
Immigration Minister Phil Woolas has pledged that the Government will not allow the population to grow to that level. But last night he was apparently undermined by his boss.
Speaking at the Home Affairs Select Committee, Mr Johnson said he would not bring in a cap because it would harm the economy, claiming the argument that immigration had made a contribution to the economy was 'irrefutable'.
'I do not lie awake at night worrying about a population of 70million,' he told the cross-party group of MPs.
'I'm happy to live in a multi-cultural society. I'm happy to live in a society where we not only welcome those coming to live and work in this country, but also where we can go and live and work in other countries.'
The Home Secretary did acknowledge the recession has made it more difficult for ministers to convince British workers who have lost their jobs that immigration is beneficial.