Finance minister P Chidambaram on Thursday said that two committees will be set up to iron out contentious issues to ease the implementation of the Goods and Services Tax (GST).

While one of the committees will deal with the compensation of the central sales tax (CST), the other will work on the design of GST.

"The committees will submit their reports by December 31," said Chidambaram, after a meeting with the empowered group of state finance ministers.

CST is collected by the Centre and distributed among states. As a pre-cursor to GST, the Centre and States in April 2007 had agreed to phase out CST over a period of three years and in line with it, the CST rate was first reduced to 3%, and then to 2%.