The Congress party on Wednesday cautioned against "hasty" implementation of the e-way Bill from February 1 to ease movement of goods under the GST regime.
The main Opposition also wanted the Modi government to hold "wider stakeholder consultations" before effecting major changes to the GST that came into force from July 1 last year.
"We are not against the introduction of e-way Bill, but it should not be introduced without adequate preparedness," Punjab Finance Minister Manpreet Singh Badal told reporters here.
While Karnataka, Rajasthan, Uttarakhand and Kerala had already started using e-way bills, Haryana, Bihar, Maharashtra, Gujarat, Sikkim and Jharkhand started trial runs on Tuesday. E-way bills will be used across the country for all inter-state movement of goods from February 1 and for intra-state movement from June 1.
The word of caution from the Congress came on the eve of the GST Council meeting that is expected to consider lowering of tax rate on a host of services and goods, particularly related to agriculture and construction sectors.
He accused the Modi government of reacting to "political compulsions" instead of wider consultations in overhauling the GST rate structure that has led to a continuous decline in GST revenues.
"The frequent revisions in filing dates have completely shattered the faith in the sanctity of the GST reform... traders have not been able to file even one full cycle of returns," Badal said.
He said even for the meeting of the GST Council on Thursday, the agenda runs into 350 pages that include revision of rates on a number of items.
Congress also made a strong pitch for bringing petroleum products and real estate under the ambit of GST, contending that several states were facing losses due to variable taxes on petrol and diesel.