22 December 2011
The Goods and Services Tax (Amendment) Act 2011, published on 20 December 2011, was passed by Parliament on 22 November 2011 and assented to by the President on 8 December 2011. It amends the Goods and Services Tax Act (Chapter 117A of the 2005 Revised Edition).
More details on the amendments can be found here.
Source: e-Gazette