CPI national secretary D Raja criticised Prime Minister Narendra Modi for describing GST as a "good and simple tax" and said only the experience of the new tax regime will show if it is "simple" or not.
Raja claimed that complaints from traders, weavers, farmers and small and medium enterprises across the country shows that the official machinery was not prepared to introduce the GST, which is effective today onwards.
Referring to Modi's "simple tax" comment, Raja said the country is entering a new terrain and none are aware of the consequences of its implementation.
"How come the prime minister says it is a simple and good tax? Nobody knows. Only the corporate sector is happy because corporate sector thinks one market and free movement of goods and services is in their interests," Raja added.
At the event held at the historic Central Hall of Parliament, the prime minister said the new "transparent" tax would end corruption and check black money.