The Congress has called a meeting of like-minded opposition parties on Friday to discuss the plight of migrant workers and the changes in labour laws by some states, sources said.
Congress president Sonia Gandhi will chair the meeting of leaders of opposition parties, the sources said on Tuesday.
Around 17 opposition parties have agreed to participate in the meeting which will be held via videoconferencing. The Samajwadi Party and the Bahujan Samaj Party have not yet confirmed their participation, they said.
Rendered jobless due to the coronavirus-induced lockdown, which began on March 25, and desperate to get home, thousands of migrant workers across the country are undertaking long and arduous journeys to their native places on foot, on bicycles or packed into trucks.
Many of them have been killed in accidents in different parts of the country.
The Opposition has criticised the government over its handling of the migrant crisis.
The Congress and other opposition parties have also attacked the Centre for allowing BJP-ruled states of Uttar Pradesh, Madhya Pradesh and Gujarat to amend labour laws to lure foreign investors and "to strip workers of their basic rights".
These changes include exempting industrial units from labour welfare statutes, allowing them to take steps such as increasing daily and weekly working hours of workers, and depriving workers of their right to move court.