The Port of Hamburg is cutting berth fees and lease charges during the coronavirus pandemic.
The German port said that owners with the most environmentally friendly vessels will see relief measures applied to "a considerable extent" as the crisis grips Europe.
The reductions apply until 30 June, based on ships' international emission classification.
Vessels that "continuously" obtained shore power from renewable energy in the port will see all fees waived.
A 90% rebate will apply for tier 3 vessels, while the figures for tiers 2 and 1 are 50% and 20% respectively.
In addition, all tenants of the Hamburg Port Authority (HPA) can apply for an interest freeze on their building and land leases.
Payments can be deferred until 31 December.
This is being done "in order to relieve the burden" on shipping companies, particularly those involved in passenger or barge operations.
"The Port of Hamburg must continue to operate without restrictions, even in the most difficult times," said the city's senator for economics, Michael Westhagemann.
"That is why we help the port companies."
Rescue measures
The package comes in addition to rescue measures put in place by the city senate for companies in Hamburg affected by the coronavirus crisis."
He added: "Quick action is necessary now. That is why I have asked the HPA for immediate implementation of these measures."
The senator for finance, Andreas Dressel, added that, especially now, the port can rely on the Hamburg city senate.
"We make what is necessary possible," he said.
The port said an informal written application is all that is required for a deferral of lease and port fees.
