Workers at the Port of Hamburg stopped work early on Tuesday, with their colleagues at Bremen-Bremerhaven taking the same action several hours later.

The trade union Verdi wants to force employers to make further concessions in pay talks with the Central Association of German Seaport Operators (ZDS).

What do we know about the strikes?

The union has called on workers in Hamburg to stage all-day walkouts on Tuesday and Wednesday ahead of a fourth round of negotiations. Negotiations for a new collective agreement for the 11,500 German North Sea port employees began in May.

The strike in Hamburg started at 6:30 a.m. local time and was set to run for 48 hours.

Employees at the commercial ports of Bremen and Bremerhaven joined the walkout on Tuesday afternoon for 24 hours, with Germany’s westernmost seaport, Emden, set to come to a standstill for a day on Wednesday.

The purpose of warning strikes, which can be staged without a ballot of union members, is to force collective bargaining in deadlocked or unproductive negotiations.

What is the union saying?

Verdi says the employers have “so far only presented an inadequate offer.”

The union has demanded “significantly better wages, especially for the lower pay groups,” with an hourly wage increase of €3 ($3.2) plus a shift allowance increase for working unsocial hours.

It says the increases are vital for workers at the lower end of the pay spectrum.

“In the third round of negotiations, we were still far apart,” said Verdi negotiator Maren Ulbrich. “The offer presented by the employers is not acceptable to us. The employers still have to make some progress, particularly on the wage increases offered.”

Ulbrich said the wage increase was increasingly necessary in light of rising inflation in recent years.

“It is important that the lower wage groups in particular are given financial relief through the wage increases. Inflation in recent years has hit them particularly hard. In addition, the wage differences between the various groups must be reduced. And there must also be an increase in real wages in the upper wage groups.”

What are the employers saying?

ZDS said that discussions so far had been “intense but constructive” and that it did not believe the strikes were warranted.

“The right to strike is enshrined in Germany’s constitution. However, when exercising the right to strike, moderation and balance should be maintained”

“In light of the constructive rounds of negotiations to date and the fair offer presented, the ZDS believes there is currently no reason for warning strikes that would compromise the reliability of German seaports.”

Warning strikes also took place at ports in June. The latest strikes come ahead of talks on Thursday and Friday of this week in Bremen.

Source: DW by Richard Connor and edited by Wesley Dockery. Material from German news agency dpa contributed to this article