Gordon Brown will concede today that Labour has made mistakes on immigration as he defends the benefits of workers coming from overseas.

The Prime Minister is expected to echo remarks by Alan Johnson, the Home Secretary, who said last week that some parts of Britain are disproportionately affected by an influx of foreigners.

In his speech today Mr Brown will say that the door is being closed to hospital consultants, civil engineers, aircraft engineers and ship’s officers from outside the European Union. He will also say that UK the population will not, as predicted, reach 70 million in the next 20 years.

“A few years ago we had to allow into the country — and we benefited from it — very highly skilled medical staff,” he has told a newspaper. “We have now done a huge amount to train a new generation of medical staff in our country. We are now looking at how we can close the skills gap in this country so we can take occupations off the list where we need to recruit from abroad. Immigration will fall.”

In the interview with the Daily Mail he explained that one of the reasons that immigration would fall is “the tightening of the new points system” which, he said, will continue to tighten over the next few months. “One of the reasons for the points system is to make sure that nobody without a skill will come into the country. We are looking at the kind of skills we as a country need.

“We don’t want as an open economy to stop businesses being able to recruit where it’s an entirely specialist area. Companies keep telling us that this is absolutely important to their future.

“This is not an arbitrary cap. We are going to be setting out a programme for making sure that we in Britain can train our British young people and British workers who are looking for jobs.”

Mr Brown will insist that Labour now has the right strategy for managing immigrants seeking work, even at a time of rising unemployment. He will acknowledge that mistakes have been made in the past. The speech will be seen as a response to the furore over the appearance on the BBC’s Question Time of Nick Griffin, the BNP leader. His fellow panellists were criticised for failing to defend the principle of migration. There are suggestions that the party could come third in today’s by-election in Glasgow North East.

Mr Brown’s remarks come days after the Tories accused the Government of trying to deceive voters over a plan to relax immigration rules.

Last month the Office for National Statistics suggested that the UK population would rise from 61 million today to 71 million in 2033. The Prime Minister is expected to promise better skills training for Britons at further education colleges in order to make them better able to beat competition from migrants.

He will highlight sectors, such as as the care industry, where he will acknowledge that more can be done to ensure jobs do not go to people from overseas. However, the approach risks reviving memories of the “British jobs for British workers” slogan in his speech to the 2007 Labour Party conference, which some colleagues suggested was inflammatory. European law prevents vacancies being reserved for Britons. Downing Street defended the speech later by insisting that he was referring to greater skills training rather than a dramatic new policy initiative.

The Prime Minister will point out that employers can recruit a migrant to a job that is not on the official list of shortage occupations only if they first go through the “resident labour market test”, showing that no qualified settled worker can fill the post.

From next year all jobs must be advertised to UK workers in job centres for four weeks rather than the current two before people from outside the EU can be hired.

Mr Johnson set out four key principles for debate last week, including that all immigrants should learn English. Distancing himself from his predecessors, he said ministers had ignored for “far too long” problems in the immigration system that led to huge backlogs of asylum seekers and foreign national prisoners.

Immigration will be the main cause of population growth over the next quarter of a century. Net migration is expected to add 180,000 to the population every year. When immigrants’ children are added, it is expected that immigration will account for 68 per cent of population growth in the United Kingdom.

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