Tata Steel has threatened to withdraw a generous redundancy package if its workers go on strike over planned job cuts.
The company made this announcement after Unite members voted in favor of industrial action, which could affect around 3,000 jobs.
Tata Steel's CEO, Rajesh Nair, stated that the "most favorable financial package" would not be paid if staff participated in the strike.
Unite, however, vowed that its members would not be intimidated by Tata's warning.
The union conducted a ballot at the UK's largest steelworks in Port Talbot and at Tata Steel's site in Llanwern near Newport.
According to Nair, 568 out of 857 union members (66%) voted in favor of the strike.
Tata Steel invited 1,366 Unite members to participate in a consultation about company restructuring, which had a turnout of 63%.
The plans include closing blast furnaces in Port Talbot and installing electric arc furnaces.
Tata Steel expressed disappointment that strike ballots were held during the consultation period and had proposed a comprehensive support package for affected employees.
Tata Steel has presented a favorable financial support package to its business, which includes enhanced employee support arrangements.
However, this offer is contingent upon the absence of industrial action within the company.
Tata Steel declined to comment further when approached by BBC Wales.
Unite, the union involved, has been asked for comment.
After the ballot results were announced, Unite Wales regional secretary Peter Hughes stated that Tata had used various tactics, including bribes and threats, to discourage industrial action from their members.