Unions urged Boeing workers to reject the company's proposals

The strike - over pay, retirement benefits and healthcare schemes - began on Friday and will severely disrupt commercial aircraft production.

Assembly workers at plants in Kansas, Oregon and Washington state downed tools after 85% of union members voted to reject Boeing's proposals.

Boeing has warned that a strike, the first since 1995, would be devastating.

Shares in Boeing fell 2.5% on Friday.

'Final offer'

The company said commercial production would cease during the strike.

"We do not intend to assemble airplanes during this strike," said spokesman Charles Bickers, adding that the company was disappointed with the outcome of the strike ballot.

If the company wants to talk, they can call me Mark Blondin, union official

Employees belonging to the International Association of Machinists and Aerospace Workers union voted down what Boeing described as its "best and final" offer.

The proposal included a 5.5% pay rise over three years, bonuses worth up to $6,000, a 10% increase in pension payments and choice of healthcare plans.

'Inadequate'

The Union had urged workers to reject the proposal, claiming that Boeing's pension and healthcare commitments were inadequate.

"If the company wants to talk, they can call me," Mark Blondin, president of the Seattle-based Machinists District Lodge 751, said after the result of the ballot was announced.

The strike will hit assembly of commercial jets and components in Seattle, Washington, Gresham Oregon and Wichita, Kansas.

The contract would have been automatically approved if it had won the support of two-thirds of unionised staff.