The march from the Gandhi statue in Parliament House to Vijay Chowk started at 1 pm.
The Opposition parties held a march in Delhi today to highlight their demand to scrap the suspension of 12 Rajya Sabha MPs and the sacking of Union Minister Ajay Mishra, whose son has been arrested in the Lakhimpur Kheri farmers' death case. The opposition parties decided on the march after a meeting this morning as part of their strategy to take forward the issues that have impeded work in the Winter session of parliament.
The march from the Gandhi statue in Parliament House to Vijay Chowk started at 1 pm.
"We are all together. We want to say that we are united and those responsible for violence against farmers must be brought to book," Congress's Rahul Gandhi said in his address at the Vijay Chowk.
"Everyone knows whose son he was and the defence is understandable, but this individual will be brought to justice," he added, referring to junior home minister Ajay Mishra's son Ashish Mishra.
The demands for Mr Mishra's sacking has intensified since the Special Investigation Team handling the case has said the killing of the farmers was a "planned conspiracy" and that it was a case of murder.
The BJP has made it clear that minister will not be asked to go.
Sources have said that the party's senior leadership is not in favour of action against Mr Mishra for now. On record, senior BJP leaders and union ministers have said the SIT is yet to submit its final report and the case is being heard in court.
On October 3, four farmers were mowed down by an SUV in Lakhimpur Kheri, allegedly by the son of the Union minister. In the violence that followed, two BJP workers and a driver were beaten to death, allegedly by the angry protesters, while a local journalist was also killed in the violence.
The other big protest of the opposition parties has been over the suspension of MPs for their unruly behavior in the monsoon session of parliament, which they have termed as "undemocratic" and against the rules of the House. Proceedings in the Rajya Sabha have been disrupted repeatedly on the matter.
This morning, Congress's Mallikarjun Kharge and Deepinder Singh Hooda gave notices in the Upper House, pressing for discussion on the Lakhimpur Keri issue. Congress MP Manickam Tagore gave a similar notice in the Lok Sabha.
"In order to ensure a free and fair trial of the murder case of innocent farmers, the Mos, who is father of the accused, must immediately be removed from his position," Mr Kharge said in his adjournment notice under Rule 267.
He also tweeted the notice, saying, "I have given a suspension of business/notice under Rule 267 to discuss the recent SIT report on the manslaughter of Lakhimpur. We demand that MoS Ajay Mishra be immediately removed from his position to ensure a free and fair trial".
The notices were, however, disallowed by Rajya Sabha Chairman Venkaiah Naidu.
Yesterday, the government's efforts to initiate back-channel talks to resolve the impasse failed as the opposition insisted on inclusion of all parties for talks and not just the four whom the government had invited.