Government immigration changes could see businesses that employ workers from abroad end up paying a heavy price, according to experts at Midlands law firm Browne Jacobson.

A new points based system, similar to one operating in Australia, will be phased in from February 29.

In some cases the fees will more than double. For example, the visa fees for skilled work-ers are set to increase by 50 per cent to £600. Fees for further leave to remain as a highly skilled migrant are expected to rise from the current £350 to £750.

Currently there are more than 80 routes by which non EU nationals can come to work in the UK. In the majority of cases an employer has to apply for a work permit. If approved the employee has to make an application for entry clearance overseas which could be refused. If that happens the employer has to start again with a new worker.

The new system consolidates the existing one into five tiers ranging from highly skilled migrants such as doctors and entrepreneurs to temporary workers and students.

Tier one caters for highly skilled migrants such as scientists and entrepreneurs. This is the first tier to be rolled out. Tier two targets skilled workers with a job offer to fill gaps for the likes of nurses, teachers and engineers. It is expected to be introduced in the third quarter. Tier three is for low skilled workers filling specific temporary labour shortages - for example, construction workers for a particular project.

Tier four takes in students. This is expected to be introduced at the beginning of 2009. Tier five covers youth mobility and temporary workers - such as working holiday makers or musicians coming to play a concert - and is also expected to be introduced in the third quarter of 2008.

Points will be awarded to reflect aptitude, experience, age and the level of need in a particular sector. Employers act as sponsors and issue a certificate of sponsorship to their prospective employee. This will enable the employee to make an application for entry clearance overseas.

Sponsors under tiers 2-5 will be required to register in advance of the system becoming operational. Fees of £1,000 will be payable by employers with 50 or more employees - £400 for charities and small employers.

A new statutory regime for preventing illegal working also comes into effect on February 29. Employers who knowingly employ an illegal immigrant could face unlimited fines and two years imprisonment.