Royal Mail PLC (LSE:RMG) staff are set to strike today and tomorrow after a call from the Communication Workers Union (CWU).
Employees who collect, sort and deliver parcels and letters will take industrial action on more dates in October, Royal Mail said.
Additional dates include 13 October, 20 October, 25 October and 28 November.
READ: Royal Mail workers to hold 19 days of strike action during build-up to Christmas
The CWU also announced “functional strike action which impacts parts of our operation”, the postal delivery service said in a statement.
That includes strikes throughout November and December for operations in processing, distribution international, collections and admin, as well as delivery and network.
“We’re sorry this strike action is likely to cause you some disruption. We will be working to get our services back to normal as quickly as possible,” said Royal Mail.
“We’ll be doing what we can to keep services running, but you should expect significant disruption on dates when strike action is taking place.”