"The champion of 'Mann ki baat' appears to have retreat into a 'Maun Vrat'," Sonia Gandhi said at a meeting of her party MPs as Parliament began a new week after a fortnight wasted in protests and disruptions.
Later today, an all-party meeting will be held to discuss a way out of the deadlock that has stalled business in Parliament.
"Today, we have to listen to sermons on parliamentary behaviour from those who not only defended but also advocated disruption as a legitimate tactic when we they were in the opposition," Sonia Gandhi said.
Aiming several barbs at PM Modi, the Congress president said he had been "very free" with his promises, "yet he seems totally incapable of delivering on them."
On one hand, she said, "he never misses an opportunity to claim the moral high ground on transparency, integrity and accountability. On the other hand he has been conspicuous by his deafening silence on the blatant transgressions by his external affairs minister and two of his chief ministers."
Sonia Gandhi's searing comments signified a hardened stand by the Congress, and a rejection of the ruling BJP's proposal that the PM "may speak" if disruptions end in Parliament.
The government has to present 11 key bills for Parliament's approval in this session, most crucial among them the General and Services Tax or GST bill.
Congress-led opposition parties are demanding the resignation of Foreign Minister Sushma Swaraj and Rajasthan Chief Minister Vasundhara Raje for having helped disgraced cricket boss Lalit Modi and of Madhya Pradesh Chief Minister Shivraj Singh Chouhan over the Vyapam recruitment scam.
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