On Wednesday, tens of thousands of dock workers across Europe went on strike to protest against a new EU directive, intended to liberalise cargo handling at seaports.
Dock workers state the directive will lead to lost jobs, lower wages and less safety.
There will be a demonstration in Strasbourg tomorrow to coincide with a discussion on the issue in the European parliament.
Supporters of the bill say it is needed to cut costs, speed up deliveries and encourage investment in ports across the 25-nation bloc.
The European Transport Workers' Federation said a total of about 40,000 people were participating in 12 countries.
4,500 German port workers took part in Wednesday's strike, which paralyzed container terminals in the North Sea port of Hamburg where 1,000 workers walked out, as reported by the ver.di union.
"Not one crane is moving," union spokesman Uwe Schroeder said. In Bremen and Lower Saxony, 1,600 workers took part in protests. Short strikes were also planned in Baltic Sea ports.
Others joined the criticism, saying the plan could damage the ports and result in job losses.
"Port Package II will not lead to more competition and higher quality in the seaports," said German Transport Minister Wolfgang Tiefensee said. "We fear that it could come to job losses in the ports on a large scale."
European dockers - victory in EU Parliament:
European Parliament protest report: