Lockheed Martin has paused production of F-35 Joint Strike Fighter aircraft in Japan and told employees at an Italian factory to work from home because of concerns over the coronavirus Covid-19 outbreak.

The production of the F-35 aircraft at the Mitsubishi Heavy Industries factory in Japan has been paused for at least one week. The move is not expected to affect deliveries.

It is the first time that weapons manufacturing has been halted by the worldwide outbreak of Covid-19, which has spread to several countries since its emergence in China in December 2019.

Most of the F-35 Joint Strike Fighters are assembled at a facility in Fort Worth, Texas, US. Final assembly and check-out (FACO) facilities for the aircraft are situated in Japan and Italy.

Lockheed Martin has also asked employees at a F-35 plant in Italy to work from home and restricted travel to the facility in Cameri, located about 30 miles west of Milan, where several international flights have been cancelled due to Covid-19 concerns.

The pause in production is not expected to affect Lockheed Martin’s plans to deliver 140 F-35 fighter aircraft in 2020.

Last week, a US Forces Korea soldier was officially confirmed positive with coronavirus Covid-19, making him the first US service member to contract the virus.

Pentagon spokesman Lt Col Mike Andrews said: “Combating the coronavirus remains a top priority for the department, and secretary Esper meets weekly with senior leaders to discuss how we’re taking care of our men and women in uniform around the world.

“The department remains fully engaged with the defence industrial base on all programs, including the F-35, and stands ready to respond when needed.”