New details of the government's radical changes to the work visa route were unveiled by the Home Office today, as it laid out the criteria for its annual limit.

This shake up is part of the government's new annual limit on non-EU workers, which will take effect on 6 April. At the end of last year the Home Office announced that 20,700 visas will be made available to skilled workers applying through Tier 2 of the points-based system, as well as 1,000 visas under a new exceptional talent route.

Under the new system, employers will have to apply for a certificate of sponsorship from the UK Border Agency for a specific post if they wish to bring someone to the UK - this is a change from the current system which gives businesses an annual allocation.

The government has also announced that employers filling a vacancy that attracts a salary of £150,000 or more will not be subject to the limit on the number of certificate of sponsorship that may be allocated.

The annual limit of 20,700 certificate of sponsorship will be divided into 12 monthly allocations. Due to the likely demand in the first month, 4,200 certificate of sponsorship will be made available in April. After that the limit will be set at 1,500 places per month. Any places that are unused each month will be rolled over to the following month.

In the event that the monthly allocation is over subscribed, certificate of sponsorship applications will be ranked using a points system designed to favour jobs on the shortage occupation list, scientific researchers and those with a higher salary. Once a certificate of sponsorship has then been granted to an employer it must be assigned to the prospective employee within 3 months.

Workers from outside the EU who want to come to the UK will need to have a graduate level job, speak an intermediate level of English, and meet specific salary and employment requirements.

The intra-company transfer route, which is not part of the annual limit, will also be changed in 3 ways:

• the job will have to be in an occupation on the graduate occupation list;
• only those paid £40,000 or more will be able to stay for more than a year. They will be granted for 3 years with the possibility of extending for a further 2; and
• those paid between £24,000 and £40,000 will be allowed to come to the UK for no longer than 12 months, at which point they must leave and will not be able to re-apply for 12 months.

Although today's statement of intent is not definitive - as the rules will be subject Parliamentary scrutiny - it is intended to provide migrants and employers with enough information to make effective plans.