New York (AFP) - Union negotiators slammed Boeing’s new offer to lift hourly wages for striking workers by 30 percent on Monday, saying it “missed the mark” and won’t be voted on by members.

“This proposal does not go far enough to address your concerns, and Boeing has missed the mark with this proposal,” union negotiators told members in a message.

“They are trying to drive a wedge between our members and weaken our solidarity with this divisive strategy.”

Boeing had sweetened its initial offer in an effort to end a 10-day stoppage that shuttered Seattle-area plants.

“We first presented the offer to the union and then transparently shared the details with our employees,” Boeing told AFP in a statement.

“We have bargained in good faith with the IAM (union) since formal negotiations began in March.”

The aviation giant gave workers until Friday at midnight to ratify its “best and final offer.”

The International Association of Machinists and Aerospace Workers (IAM) said there wasn’t enough time to discuss the offer with members and tend to the voting before the Boeing deadline.

“The company has refused to meet for further discussion; therefore, we will not be voting on the 27th,” union negotiators told members.

The union noted it will gather workers’ opinions regarding the offer.

About 33,000 IAM members from District 751 in the Pacific Northwest region walked off the job on September 13 after overwhelmingly voting down an earlier offer, effectively shutting down assembly plants for the 737 MAX and 777.

The 30 percent general wage increase improves on the 25 percent in the earlier offer, which was initially endorsed by IAM leaders before the rank-and-file workforce rejected it decisively.

Workers have sought a 40 percent wage increase, citing more than a decade of meager pay boosts that have taxed family budgets in a costly region of the United States during a period of consumer price inflation.

The new proposal also reinstates an annual bonus that had been removed in the earlier version.

Line workers had complained that the loss of the bonus meant that the earlier proposal amounted to less than the 25 percent wage hike advertised by the company.

The new proposal also doubles a ratification bonus to $6,000 and lifts the company’s contribution to employees’ 401K program. But the amended offer does not reinstate the pension, a demand of some workers.

The two sides undertook two days of mediation last week with assistance from government officials.

Boeing CEO Kelly Ortberg said ending the strike was “a top priority.”

- Boeing ‘could do better’ -

Surveys of line workers have shown general wages, the reinstatement of the bonus and the pension as priorities, the IAM has said.

Brian Bryant, president of the IAM international union, said the latest offer from Boeing “validates” the decision to strike.

“Employees knew Boeing executives could do better, and this shows the workers were right all along,” Bryant said in a statement.

Boeing employee Mike Corsetti said he looked forward to studying the proposal in detail, saying, “it’s closer but I’m not sure it’s good enough.”

The amended deal maintains other provisions, such as a pledge to build Boeing’s next new airplane in the Pacific Northwest.

The strike has added to Boeing’s woes as it faces heavy scrutiny from regulators due to safety problems.

Federal Aviation Administrator Mike Whitaker is scheduled to sit for two congressional hearings this week on the agency’s oversight of Boeing.

Shares of Boeing ended the formal trading day up two percent.