sympathy strike

Translations
забастовка солидарности
The union called a sympathy strike to support their fellow workers.
Профсоюз объявил забастовку солидарности в поддержку своих товарищей по работе.
Definitions
A sympathy strike is a work stoppage by employees who are not directly involved in a labor dispute but choose to strike in support of other workers who are on strike, often to show solidarity or to put additional pressure on the employer.