The British government on Monday announced a series of measures to favor "British jobs for British workers" campaign pledged by British Prime Minister Gordon Brown.
Home Secretary Alan Johnson said on Monday that British firms will have to advertise jobs in Britain for at least a month before they can offer them to workers from outside Europe.
The measures are among 16 proposals put forward by the Migration Advisory Committee. Johnson said he was altering the rules in response to rising unemployment in Britain.
In other moves, Johnson is also increasing the salary that employers have to offer to someone who enters Britain by qualifying as a skilled worker from 17,000 pounds a year to 20,000pounds.
In addition, he is extending from six months to a year the period that overseas workers have to work for a firm before they become eligible to transfer to the company's British base.
It is estimated that one in 10 of the non-European Union workers given permits last year would be excluded under the new rules.
Johnson said: "These changes will ensure that businesses can recruit the skilled foreign workers that the economy needs, but not at the expense of British workers, nor as a cheaper alternative to investing in the skills of the existing workforce."
In August, the British government also carried out a consultation on the new citizenship proposals, which "require people to earn points for, among other things, their skills, their job and their qualifications." And only those with enough points will earn the right to a British passport.