Boeing has filed unfair labor practice charges with the National Labor Relations Board on Thursday, accusing union leaders of bargaining in bad faith on behalf of striking machinists.

Beoing had stated in a statement that the union “did not seriously consider” its latest proposals that included improvements to its initial offer which it had called its “best and final” and claimed that the union “continues to insist on unreasonable demands.”

“The union’s public narrative is misleading and making it difficult to find a solution for our employees,” the company said.

The strike, which saw some 33,000 workers walk off the job on Sept. 13, is now in its fourth week, with no end in sight. The union has slammed Boeing’s offer, which included 30% pay raises for workers, as disrespectful. It has argued that its workers need a 40% wage hike to combat the cost of living, a return to the pension system it gave up in a 2014 deal, more input on product safety, and other benefits.

Jon Holden, lead negotiator for IAM District 751, told Reuters on Wednesday that the Virginia-based company is “trying to take credit for very minor, very meager movement that wasn’t really touching on the major issues.”

“We’re in this for the long haul and our members understand that” Holden said, doubling down on the union’s hardline stance against the aerospace giant.

That’s in response to several unfair labor practice charges levied against the aerospace giant by the International Association of Machinists and Aerospace Workers (IAM), the union representing the striking workers.

As the strike continues, its economic impact grows. There’s already some worry that it will impact the November jobs report. In addition to the more than 30,000 workers who walked off the job, Boeing has initiated furloughs. Boeing’s issues which began this year with an almost catastrophic incident involving a 737 Max 9 jet that led to intense scrutiny of its operations may also have repercussions for Boeing suppliers.

“The recent hurricane in Florida and the Carolinas and the Boeing strike have the potential to weigh on GDP growth for the remainder of the year,” Oxford Economics analysts wrote in a recent note.

S&P Global Mobility on Tuesday estimated that Boeing will incur a cash outflow of roughly $10 billion in 2024, partially due to the strike and measures taken to overhaul its manufacturing process and issued a negative outlook for the company’s credit ratings. Boeing is expected to burn about $50 million a day in cash because of the strike.