Germany's interior minister on Sunday said the country would increase controls on the border with Poland, as police broke up an armed group of far-right activists trying to prevent migrants from entering.
Horst Seehofer told the Bild am Sonntag newspaper that 800 police had already been deployed on the German-Polish border to help deal with a recent increase in migrants crossing into Germany from Belarus.
"If necessary, I am ready to reinforce this even more," he added.
Police on Sunday broke up around 50 activists from the radical far-right group "The Third Way" (Der III. Weg), which had called for its members to gather to take action against migrants seeking to cross the border from Poland.
During the operation, police seized pepper spray, a bayonet, a machete and batons.
A recent surge in people crossing illegally over the EU's eastern frontier with Belarus has placed major strains on member states.
Poland has proposed building a 350 million euro ($410 million) wall on its border with Belarus to keep migrants out.
Asked whether such border walls were necessary, Seehofer said: "It is legitimate for us to protect the external border in such a way that undetected border crossings are prevented."
According to figures from the German interior ministry, around 5,700 people have travelled over the border between Germany and Poland without an entry permit since the start of the year.
On Saturday, a suspected smuggler was taken into custody after 31 illegal migrants from Iraq were found in a van near the Polish border.
Seehofer wrote to his Polish counterpart Mariusz Kaminski last week to propose increasing joint patrols along the border with Poland in response to rising numbers of migrants.
Kaminski responded that Poland would offer its "full support" for such measures.
However, Seehofer also said last week Germany had no plans to close the border with Poland, adding that such a move would also be "legally questionable".
The EU accuses the Belarusian authorities of flying migrants from the Middle East and Africa to Minsk and then sending them into the bloc on foot in retaliation for sanctions imposed over a crackdown on the opposition.
Earlier this month, officials from countries including Poland, Lithuania and Greece argued for barriers along EU borders to counter efforts to weaponise migration.
Brussels has so far shied away from funding border walls for members states, insisting that the current legal framework only allows it to use EU budget funds for "border management systems".
