Germany said on Monday it would extend stepped-up border controls beyond March 2025, amid a security and immigration debate following a deadly Christmas market attack and ahead of February elections.
In mid-September, Berlin imposed controls with all nine neighbouring countries for six months, aiming to curb irregular immigration and heighten security after a deadly knife attack with a suspected jihadist motive the previous month.
Since then, around 1,800 people have been arrested and 40,000 turned back at Germany's land borders, Interior Minister Nancy Faeser told the newspaper Augsburger Allgemeine.
Europe's biggest economy has already had border controls in place for several years with Austria, Poland, the Czech Republic and Switzerland.
On September 16, it also started operating police checkpoints along its borders with France, Luxembourg, Belgium, the Netherlands and Denmark.
"We need these controls until the protection of the EU's external borders is significantly strengthened," Faeser said on Monday.
She added that the number of deportations of rejected asylum seekers had gone up by more than 50 percent in the past two years.
Germany is the only country in Europe to have "deported dangerous criminals to Afghanistan", said Faeser, vowing: "We will continue this."
On Syria, where President Bashar al-Assad was ousted this month, she said: "If the hope for peace in Syria becomes a reality, then many refugees will be able to return."
The government of centre-left Chancellor Olaf Scholz, whose coalition collapsed in November, faces elections on February 23.
Security and immigration have become major election issues after a series of deadly attacks this year.
Three people were killed and eight wounded in a stabbing spree at a street festival in the western city of Solingen in August.
The attack was claimed by the Islamic State group and police arrested a Syrian suspect.
On December 20, a car ploughed through a Christmas market crowd in the eastern city of Magdeburg, killing five people and wounding over 200.
Police arrested a 50-year-old Saudi doctor of psychiatry who espoused far-right, anti-immigrant views, but have yet to declare what the suspected motive was.
In his many online posts, suspect Taleb al-Abdulmohsen voiced strongly anti-Islam views, anger at German authorities and support for conspiratorial far-right narratives about the "Islamisation" of Europe.
Security officials have said in the past that homegrown far-right violence has become Germany's biggest extremist threat, including a group arrested last year accused of plotting to attack parliament and overthrow the government.