Left parties and their affiliated trade unions will mount pressure on the government, inside and outside Parliament, to seek reinstatement of 500 Maruti Suzuki workers sacked in connection with the violence at its Manesar plant.
The pressure tactics may include Left's demand for adjournment of Parliament's regular business to take up the issue.
The trade unions may also approach the court, challenging the company's decision to terminate 500 permanent workers.
Major central trade unions, including CPI-affiliated All India Trade Union Congress (AITUC) and CPM-affiliated Centre of Indian Trade Unions (CITU), will meet on Tuesday to plan a rally in the National Capital to press for their demands.
"We do not expect any positive response from the Haryana government. We are planning to take it to the national level and pressurise the central government. The Left parties, along with other like-minded parties, will press for an adjournment in Parliament," AITUC national secretary DL Sachdev said.
He said: "The company can't take such a major decision without consulting the state government."
Rajya Sabha member Tapan Kumar Sen (CPM) had, last week, raised the issue in the house, terming removal of workers "vindictive and retaliatory".
JMM MP Sanjiv Kumar had demanded a CBI probe into the violence.
"We are planning a rally in Delhi and a march to Parliament. We will bring in all workers from nearby areas and stage a protest on a suitable day, which will be decided at the central trade union's joint meeting on Tuesday," Sachdev said.
Expressing similar sentiments, CITU Haryana state president Satvir Singh said the unions had given an "ultimatum" to the state government till Tuesday for reinstatement of the sacked workers.
"After that, we will study the termination notices and may consider approaching the court for a stay. We will do everything possible for justice," he said.
Workers at MSI's Gurgaon plant, under the aegis of Maruti Udyog Kamgar Union (MUKU), have also opposed the mass sacking.
"We will consult lawyers and consider legal options," MUKU general secretary Kuldeep Jhangu said.
Following the violence on July 18, in which one senior official was killed and nearly 100 others were injured, the company declared a lockout at Manesar plant on July 21. The month-long lockout will be lifted on Tuesday with resumption of partial production.