The IT industry is concerned that changes to Home Office rules will make it harder to plug skills gaps by recruiting skilled migrants from abroad.

From next year, all jobs must be advertised in the UK for four weeks ­ – up from two ­ – before companies can look overseas. The minimum salary qualifying someone as a skilled worker will rise from £17,000 to £20,000 and overseas workers wanting to transfer internally to the UK must have worked for their employer for at least a year ­ – up from six months.

The moves will affect the IT sector more than most. Early government data for 2009 shows that about one-third of all so-called Tier 2 applications to the UK are for IT professionals. By industry, IT activities account for about 35 per cent of Tier 2 applications, the vast majority of which are for computer programming, consultancy and related activities.

The points-based immigration system was set up to balance the need for overseas workers against the social impact of staff coming in from abroad, and the new measures tread that line successfully, according to Guy Bailey, senior policy adviser on employment issues at the CBI.

“The measures recognise that there are skills shortages that need to be filled, but with so many out of work, that the jobs could be filled by British workers first,” he said.

Bailey believes the measures will not have a big impact on businesses. An additional two weeks in the recruiting process will not be a vast concern for most employers, while most Tier 2 appplicants are likely to have worked for their company for at least a year.

But some experts have predicted the new model will lead to a reduction of as much as 10 per cent in the influx of Tier 2 workers.

While the plans may seem to be giving 10 per cent more jobs to UK workers, many firms feel they will not enhance the UK’s international competitiveness in the long run.

They argue that having more skilled workers from overseas means UK workers must raise their game. Meanwhile, homegrown talent will be more available to smaller companies rather than being grabbed by large firms.

The Migration Advisory Committee, which recommended the new policies, recognised these issues as a potential problem.

“In the long run, further efforts should be made to upskill the UK workforce to do these jobs. In the shorter term, consideration should be given to how investment in training and pay budgets can respond more flexibly to regional and occupation-specific shortages and, where such flexibilities exist, ensuring that employers use them,” it says in its report on the issue.

And the new rules could have an effect beyond the skills market, according to Carrie Hartnell, head of industry strategy at IT trade association Intellect.

“An increase in fees will drive smaller firms to seek other, possibly illegal routes for overseas workers, and enforcement efforts have not been stepped up to compensate for this,” she said.

And companies that need to upskill quickly for a particular project will be delayed in assembling the talent they need ­ – even when they know it does not exist in the UK. But much of the devil lies in the detail. Intellect is working with the UK Border Agency to ensure that the rules are put in place with as little red tape as possible, and the agency is being receptive.

“We need to make sure these workers do not have to fill in an 18-page document each time they move,” said Hartnell.