The biggest tax reform in decades - the national Goods and Services Tax or GST - has been thoroughly jeopardized by the centre's abrupt demonetization drive, said Amit Mitra today. As the Finance Minister of West Bengal, Mr Mitra is on the GST Council, which is drafting the rate and scope of the tax. He told NDTV that the April rollout of the tax seems unfeasible now and he will talk to other Finance Ministers about revisiting support for a reform seen as crucial for economic growth.