Locked-out union members are blasting National Grid for stopping payment to their health care plans, but the company says it won’t give out benefits while the workers refuse to give up the ability to strike.

National Grid locked out more than 1,000 members of United Steelworkers Locals 12003 and 12012 on June 25 after contract negotiations broke down, and is using managers and outside contractors to oversee complaints during the stoppage. The two sides have clashed over National Grid’s proposed changes to the company’s health care plan and benefits for new hires.

The workers have not received wages, but as of July 1 are no longer getting health care through the company, Local 12012 president John Buonopane said, and while the union is trying to use its emergency medical plan and register people with MassHealth, he was concerned workers without coverage may choose not to address medical issues.

“None of this is easy on anybody, it’s a shame the company is taking a hard stand,” Buonopane said. “We’re hoping to eventually get everyone covered, but it’s not going to happen right away. I would hate to hear of someone avoiding having treatment for an issue because they don’t have the health care right now. That’s a real possibility.”

National Grid spokesman Robert Kievra said the company has been bargaining in good faith but began the lockout to prevent any strikes that could affect safety, and the company is looking to negotiate a no-strike clause as well as add deductibles and coinsurance to employees’ health plans.

“Currently, employees in these two unions, unlike the overwhelming majority of our unionized employees in Massachusetts and other states, enjoy health insurance plans with no deductibles or coinsurance,” Kievra said in a statement. “In the absence of a tentative agreement on all outstanding issues, which would include a no-strike promise, the company made the difficult decision to implement its work continuation plan to ensure uninterrupted and safe gas service for our customers until we reach a final agreement.”

Buonopane said the health care cut was a negotiating tactic.

“I’m definitely surprised they cut health care, especially so quick,” Buonopane said. “It’s definitely a bargaining position to pressure people into accepting their offer.”