A German flag flutters next to the ships at the loading terminal in the port of Hamburg

Dresden - Dozens of German mayors signed a joint declaration on Friday as an act of protest against a neo-Nazi music festival set to take place in the eastern town of Ostritz on April 20 to mark the birthday of Nazi dictator Adolf Hitler.

"Those who question human rights and those opposed to democracy and pluralism are not welcome here - they will not be made to feel at home in our region," reads the declaration, which the 40 town mayors handed over to Saxony premier Michael Kretschmer on Friday.

The "Schild und Schwert Festival" (German for Shield and Sword Festival) is being held on private property in the Saxon town of Ostritz on April 20, with around 800 people set to attend.

On its website, the festival lists a series of politicians from right-wing extremist fringe parties, including the National Democratic Party (NPD) and Die Rechte, as speakers at the event.

Celebrations marking Hitler's birthday are common within neo-Nazi subcultures around the world.