Boeing said on Tuesday it delivered 33 jets in September, down from 40 plane deliveries in August, as a strike mid-month by around 33,000 U.S. West Coast factory workers weighs on output.

Boeing Co. managed to hand over 33 aircraft to customers in September, when a strike shut down large parts of its manufacturing, while warning that the work stoppage at its main production hub in the Seattle area will reduce future deliveries.

Boeing delivered fewer airplanes in September compared with recent months and past years, as it felt the first effects of the ongoing Machinists strike.

A machinist strike is now in its fourth week, halting work at Boeing's factories in the Seattle area. Boeing delivered 33 airplanes in September, six more than during the same period a year earlier, as the company and its customers keep an eye on the impact of a machinist strike,

Boeing delivered 33 new aircraft to customers in September in spite of a labor strike of Seattle-area workers that has shuttered two major assembly plants, the company said Tuesday.