Braving mosquitoes and the heat, five suspended MPs, including Communist Party of India's Santosh Kumar and Aam Aadmi Party's Sanjay Singh, spent the night near the Gandhi statue in Parliament complex.
Trinamool Congress's Dola Sen and Santanu Sen were present at the site till post midnight.
With authorities not granting permission for a tent, five MPs slept under the sky as a protest against the suspension of 24 MPs, 20 from Rajya Sabha and four Congress members from Lok Sabha.
'50 hour non-stop dharna by Opposition MPs. 21 hours done. 29 hours to go.
'Revoke suspension of 24 MPs. Discuss,' tweeted TMC Rajya Sabha MP Derek O'Brien.
In the Thursday morning, TMC MP Mausam Noor who brought tea for the MPs said that the Opposition MPs will not apologise and the protest will continue.
"There is no question of apologising. We want to have discussions on price rise in Parliament but we were suspended. Our 50-hour-long protest will continue outside," said Noor.
Her comment came after Union Minister Pralhad Joshi's statement that suspension can be revoked if Opposition MPs apologise.
Another TMC MP Shanta Chhetri also hit out at the government saying they were only raising issues of the common people.
"We are not going to apologise as we haven't done anything wrong. We've raised the issues of common people. The country is suffering from price rise and raising the issue is not wrong," said Chhetri.
Meanwhile, a meeting of Opposition parties was held to discuss the issue of suspension of MPs.
However, the AAP and the TMC skipped the meeting.
Leader of Opposition in Rajya Sabha Mallikarjun Kharge said that the Opposition will submit a request to the Speaker of Lok Sabha and Chairman of the Rajya Sabha to rescind the suspension of the members who raised their voices against the price rise.
Speaking to ANI, Kharge said, "The issues that we have been raising since the last 7 days regarding inflation and imposition of GST on essential commodities, today on the eighth day also we will raise our voice regarding the same. Common people are worried about this.
"We are also raising our voices continuously, but the government is not ready for discussion. I personally met the chairman and said that you allow the discussion and tell the date and time, we will be ready for discussion, but the government is not ready to accept it.
"We will submit a request to the Speaker and the Chairman to rescind the suspension of the members who raised their voices against the price rise."
He further said that the suspension of MPs which has been done at the behest of the government and should be withdrawn with immediate effect.
-- with ANI inputs
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