The British government plans to announce details Tuesday of a new, points-based immigration system that will favor those with needed skills, reported AP. The new system, which is expected to come into force in the middle of next year, will apply to citizens of countries outside the European Union and the European Economic Area. It will not apply to refugees or asylum cases, however. Ministers have previously indicated that the system will be based on four tiers, with those in the top tier having the best chance of gaining permission to immigrate: _ First tier: Highly skilled migrants including doctors, engineers, information technology specialists and finance experts will be admitted without having to secure a job offer in Britain first. _ Second tier: Skilled workers with qualifications including nursing, teaching and administration may be admitted to areas of Britain with specific skills shortages. _ Third tier: Low-skilled workers who can be admitted for a strictly limited time. _ Fourth tier: Students and special categories including professional athletes and employees of international companies based in Britain.