CPI-M leader Sitaram Yechury on Thursday said Finance Minister Arun Jaitley's 2018-19 budget was "unconnected to ground realities".
In his reaction to Prime Minister Narendra Modi government's last full budget before the next Lok Sabha election, Yechury said it "is a textbook exercise in post-truth".
Jaitley said India was poised to become a $5 trillion economy soon.
The most ambitious announcement appears related to covering 50 crore people under health insurance. Up to five lakh rupees per family. A universal health coverage would have been more ambitious.
Key Indian equity indices fell from their highs to trade in the red during the mid-afternoon trade session on Thursday as Finance Minister Arun Jaitley presented the Union Budget 2018-19 in Parliament.
Heavy selling pressure was observed in consumer durables, metals and healthcare stocks.
At 12.16 p.m., the wider Nifty50 of the National Stock Exchange (NSE) fell by 17.60 points or 0.16 per cent to trade at 11,010.10 points.
On the BSE, the barometer 30-scrip Sensitive Index (Sensex) fell below the 36,000-mark to trade at 35,880.47 points -- down 84.55 points or 0.24 per cent from its previous close.
However, the BSE market breadth was bullish with 1,364 advances and 1,161 declines.
On Wednesday, the benchmark indices closed in the negative territory on the back of negative global cues and heavy selling pressure in healthcare, consumer durables and capital goods stocks.
The Nifty50 fell by 21.95 points or 0.20 per cent to close at 11,027.70 points, while the Sensex closed lower by 68.71 points or 0.19 per cent at 35,965.02 points.