Beginning 6 April 2012 the UK Border Agency (UKBA) will require all applicants applying to remain in the UK under Tier 1 (General), Tier 1(Entrepreneur) and Tier 2 of the UK points-based system to have a completed language test prior to applying for a visa.
According to UKBA, applicants applying for leave to remain will continue to be able to take advantage of the concession for visa applications received up to and including 6 April 2012. Visa applications made after 6 April 2012 must be accompanied with evidence that applicants have passed an approved English language test.
In addition, UK immigration has released a new list of approved English language test providers for visa applications made under Tiers 1, 2 and 4 of the points-based system.
Effective 24 January 24 2012, further amendments were made.
Source: Global Visas
very good to know!