Striking Boeing workers have been told they could bring the aircraft giant to its knees and see themselves laid off in their thousands.

Chief executive Jim McNerney gave the stark warning in emails to workers this week over a strike which ironically is being welcomed by several airlines.

While collapsing morale and industrial relations is threatening to derail the production of Boeing's all-new 787 Dreamliner project, dozens of airlines around the world, notably Ryanair and British Airways, who signed up to buy hundreds of Boeing aircraft in coming months and years will be happy to have their delivery schedules delayed. Ryanair is contracted to take delivery of dozens of 737s, while BA is getting new aircraft to replace its ageing 747s.

In an attempt to prod Boeing employees back to work McNerney told them: "US auto companies all but fatally wounded themselves years ago by promising unsustainable wage and benefit levels and by agreeing to contract conditions [including job guarantees] that limited their flexibility to run their businesses in the face of intense global competition.

"Today their market shares continue to fall and their lay-offs have grown by the thousands."

McNerney held out the threat that Boeing could be superseded by the European giant Airbus as the world leader in commercial aviation.

Boeing has been locked in a month-long strike with 27,000 workers which has halted production at its plants in Seattle. Arbitrators have been brought in to try to break the deadlock and the machinists' union is understood to have agreed to meet federal mediators.

Members of the International Association of Machinists and Aerospace Workers walked out over fears that Boeing's outsourcing of the production of many components would lead to job losses. However, signals from the company are that McNerney will not cave in and if progress is to be made it will have to come from union concessions.

Boeing shares have crashed in recent days to a four-year low and analysts are predicting that every month on strike costs the company $2.8 billion in lost revenues.

The Dreamliner, Boeing's first all-new aircraft in a generation, is already 14 months late because of various delays.