"We continue to engage in a constructive dialogue with the European Commission and believe our proposals address their concerns, and still very much support the industrial logic of the joint venture," said a Tata Steel spokesman in an emailed statement to Reuters.

Tata Steel and ThyssenKrupp had proposed to combine their steel operations in Europe, which would form the region's second-biggest steelmaker. However, the deal has not been approved because of concerns about its impact on competition.

The European Commission has said the deal could limit competition in the markets for steel for car parts, packaging such as food and aerosol cans and electrical steel for engineering products including transformers.

Under the new proposal, which is yet not public, both the companies will be selling some units across Europe to meet the Commission's antitrust criteria, Reuters reported last month.

However, the companies are unlikely to make further concessions to win approval, a source familiar with the matter said on Tuesday. The European Commission will review the proposals until June 5.

Guido Kerkhoff, ThyssenKrupp's Chief Executive, said in February that if the joint venture is not approved, "It won't kill us."

However, Tata Steel stands by the merits of the deal. "We're committed to working closely with all relevant regulators and remain confident of the benefits of the joint venture to all our stakeholders," the statement said.