New Delhi | Opposition parties on Sunday stepped up their attack on the Modi government over the Adani issue, with the Congress alleging that its "silence smacks of collusion".

Ahead of the party's planned nationwide protests on Monday, Congress General Secretary (Communications) Jairam Ramesh said they will pose three questions a day to Prime Minister Narendra Modi over the issue and "your government cannot hide from saying 'HAHK' (Hum Adani Ke Hain Kaun)”.

What action has been taken, if ever, to investigate the serious allegations made over the years against the Adani Group and is there any hope of a fair and impartial investigation in the matter under the prime minister, he said in a statement and asked the prime minister to break his "silence" over the issue.

Telangana Chief Minister and BRS leader K Chandrasekhar Rao endorsed the demand of opposition parties for a Joint Parliamentary Committee (JPC) to look into the "scam", while BSP chief Mayawati said India's image is at stake but the government is taking the issue "very lightly".

Adani group stocks have taken a beating on the bourses after US-based activist short-seller Hindenburg Research made a litany of allegations including fraudulent transactions and share price manipulation against the Gautam Adani-led group which has dismissed the allegations as lies.

Ramesh said that amid the allegations against the Adani Group, the Modi government has maintained a "loud silence which smacks of collusion".

He alleged Vinod Adani, the brother of Gautam Adani, was named in the Panama Papers and the Pandora Papers as someone "who operates offshore entities in the Bahamas and the British Virgin Islands".

"What does the fact that a business entity you are well acquainted with faces serious allegations tell us about the quality and sincerity of your investigations?" the Congress general secretary said.

"How is it possible that one of India's largest business groups, one that has been allowed to build monopolies in airports and seaports, could have escaped serious scrutiny for so long despite persistent allegations?" Ramesh said.

Other business groups have been harassed and raided for much less, he alleged.

"Was the Adani Group essential to a dispensation that has profited from 'anti-corruption' rhetoric all of these years," Ramesh said.

Tagging his statement, the Congress leader tweeted, "The eloquent silence of the PM on the Adani MahaMegaScam has forced us to start a series, HAHK-Hum Adani Ke Hain Kaun. We will be posing 3 questions to the PM daily beginning today." The opposition parties have alleged that the recent meltdown in Adani Group shares is a scam that involves common people's money as public sector LIC and SBI have invested in them.

The Congress will hold district-level protests outside all offices of SBI and LIC on February 6, party general secretary K C Venugopal had announced earlier.

Parliament was adjourned for the second consecutive day on Friday without transacting any business after the Opposition raised slogans demanding a discussion and a JPC probe into the issue.

On Sunday, Trinamool Congress (TMC) leader Derek O'Brien said his party wants debate not disruption in Parliament and is raring to take on the government.

He said that if any party disrupts the House it is in cahoots with the BJP.

"BJP scared. Trying to RUN AWAY FROM DEBATE in Parliament. Great chance to skewer Modi Govt from Mon Feb 6 when both Houses debate President's Address Keep a close watch. If any Oppn party disrupts, they are in CAHOOTS WITH BJP, We TMC want debate, not disruption," the Rajya Sabha MP tweeted.

Union Information and Broadcasting Minister Anurag Singh Thakur has said the government has nothing to hide on the Adani issue and accused the Opposition of evading discussion in Parliament.

The 10 listed Adani group firms have faced a combined erosion of over Rs 8.5 lakh crore in just six trading sessions. Adani Enterprises also had to withdraw a Rs 20,000 crore share sale.

"It is going to have a long-term impact on the country's economy and common life. Yet like in other cases, in this issue also the government is not taking the people of the country into confidence through the House. It is sad," Mayawati said.

Telangana Chief Minister Chandrasekhar Rao alleged the Centre has pressured Life Insurance Corporation to make a false statement over its exposure in the Adani Group.

The Indian banking system is involved in this problem and the whole country is worried, he said.

Addressing a press conference in Nanded city of Maharashtra after speaking at a public rally, Rao said, "It is my request to the Prime Minister that Adani Group is involved in such a big scam and it should be discussed in a joint parliamentary committee".

"Everyone knows he (Adani) is your friend. In just two years, he became the world's second richest person. If you are honest, set up a joint parliamentary committee. It is my demand," Rao said.

He said India has enough reserves of coal that would last for the next 120 years but the Union government is forcing states to procure imported coal, which is only supplied by the Adani group.

"The kind of love the Centre has for Adani, it should have for the people of the country," he said.

Bihar Chief Minister and JD(U) leader Nitish Kumar had on Saturday said that allegations against the Adani group "should be looked into".

The Adani group has maintained it complies with all laws and disclosure requirements.

Finance Minister Nirmala Sitharaman has said that regulators Sebi and RBI should always be on their toes to keep the equity market stable and indicated that the Adani stock rout following the Hindenburg report was a company-specific issue.

She said banks and insurance companies are "not overexposed" to any one company and assured that Indian markets are very well managed by its regulators.