A cross party group of MPs has warned today's introduction of a points-based immigration system will not stop tens of thousands of non-EU migrants coming to the UK.
The Government claims the change in the law will narrow the list of occupations which companies can fill with workers from outside the European Economic Area.
Frank Field MP and Nicholas Soames MP, co-chairmen of the Cross Party Group on Balanced Migration, said: "Today certainly marks a major reconstruction of the immigration system which has been in a state of collapse.
"That is to be welcomed, but no amount of spin can hide the fact that the points based system will not stop tens of thousands of non-EU migrants coming to the UK and competing with the British unemployed for work; and will not stop our population from reaching 70 million by 2028.
"The Government admits that at best last year it might have cut 12,000 from net immigration of 237,000. This is a finger in the dyke - not the radical action that we urgently need to bring migration into balance, and stabilise the size of our population."
The Government's move follows an interview given in October by immigration minister Phil Woolas who said the number of migrants coming to Britain must be curbed to control population growth.
He said increasingly tough economic conditions made immigration "extremely thorny" and warned the Government would not allow the population to expand endlessly.
Speaking to The Times, Mr Woolas said: "It's been too easy to get into this country in the past and it's going to get harder."
Figures released earlier this month by the Office for National Statistics (ONS) said the estimated number of people arriving to live in the UK for 12 months or more was 577,000 in 2007, compared with 591,000 in 2006.