“Workers in the distribution companies sector are to put into effect a nationwide strike on the 23rd and 24th of December of 2017, from midnight to midnight," the FEPCES, which is affiliated to the CGTP trade union confederation, Portugal's largest, in a statement.

According to the federation, the strike is over the collective employment contract in force in the sector, salaries, automatic promotions for warehouse workers, and rules on working hours.

It said that services necessary for the security and maintenance of equipment and premises will be carried on during the period of the strike.