The 26,800 members of the Seattle-area International Machinists and Aerospace Workers voted overwhelming to strike earlier this week, saying they weren't satisfied with Boeing's offers on pay raises, healthcare coverage and job security, the Wall Street Journal reported.

The walk-out was delayed for two days after a federal mediator asked the union to continue talking with company representatives. The IAM last struck for 24 days in 2005, the newspaper said.

"Despite meeting late into the night and throughout the day, continued contract talks with the Boeing Company (NYSE:BA) did not address our issues," Tom Wroblewski, the union's district president, said in a statement.

"Over the past two days, Boeing, the union and the federal mediator worked hard in pursuing good-faith explorations of options that could lead to an agreement. Unfortunately the differences were too great to close," Boeing Commercial Airplanes President Scott Carson said in an e-mail to employees.