Authorities in Poland on Monday began carrying out random checks at 52 border crossings at the country's border with Germany, in a move seen as contrary to the spirit of the European Union's visa-free Schengen zone.

The new checks come after stricter German controls at the Germany-Poland border, which have been stepped up under Chancellor Friedrich Merz's government. 

The Polish border checks, which also apply to 13 crossings along Poland's border with Lithuania, are set to run initially until August 5.

Why is Poland patrolling its borders? 

Polish Interior Minister Tomasz Siemoniak said Sunday the controls were meant only to combat "illegal immigration" and that Polish and other EU nationals would not face hindrances.

The controls will reportedly focus on buses, minibuses, cars carrying large numbers of passengers and vehicles with tinted windows.

Siemoniak on Sunday said "illegal migration is simply a crime," noting that Polish border guards had immediately arrested an Estonian man attempting to deliver Afghan migrants into Poland across its border with Lithuania on Sunday night after the new control regime went into effect. 

Siemoniak said the arrest was, "proof that these checks are necessary."

Before Poland's announcement, the German government said it would begin turning back asylum-seekers at the Polish border, leading to claims by Polish nationalist and far-right politicians that Berlin is overwhelming Poland with migrants.

Later Monday, Siemoniak told reporters that "if Germany lifts its controls, we are not going to delay either." 

'We're doing this for you,' Poland's Tusk tells EU partners

On Monday, Polish Prime Minister Donald Tusk, speaking at a press conference alongside Netherlands Prime Minister Dick Schoof, said: "We're doing this for you as well. For the Germans, the Dutch, for the French ... because this is the European Union border."

Tusk was referring to the EU's eastern border to Belarus, which has in the past been the scene of great confusion as Minsk has been accused of facilitating migrant crossings into the EU as a way of socially and politically destabilizing the bloc.

Since May 8, German officials have refused entry to around 1,300 people on the border to Poland, according to the German Interior Ministry, with one in 10 cases involving an asylum request.

EU rules on the Schengen area stipulated that countries are allowed to introduce temporary measures as a "last resort" and "in exceptional situations."

On Monday, Chancellor Merz's spokesman Stefan Kornelius said, "The protection of borders against irregular migration is an interest that Germany has, that Poland has, that our European neighbors share with us." 

"We do not," added Kornelius, "want permanent border controls."

Speaking of the situation during a visit to the Czech Republic on Monday, German Foreign Minister Johann Wadephul defended Germany's approach, while calling for a EU-wide solution to the problem of illegal migration.

"I believe that irregular migration affects us all and that we therefore need more order, including more order within and with Europe," said Wadephul in Prague. 

Though the Czech Republic has yet to introduce border controls, Foreign Minister Jan Lipavsky said Prague and Berlin had found "significant convergence" on their views toward migration, among other issues.

Edited by: Wesley Rahn