Royal Mail’s attempt to hire 30,000 casual workers to help break the strikes hit trouble last week as job centres refused to advertise their vacancies.
A memo from top civil servants to job centre managers says helping the company is “potentially illegal” and that recruitment ads must “immediately be suspended”.
Royal Mail’s job ads will be taken, but not shown publicly.
The law forbids companies from replacing strikers with temporary staff. The CWU union plans to test the law by taking Royal Mail to the high court later this week.