Polish Foreign Minister Zbigniew Rau accused on Sunday German Chancellor Olaf Scholz of attempting to interfere in the internal affairs of Poland.

On Sunday, Scholz did not rule out tightening measures at the external borders of the European Union to prevent illegal migration amid a corruption scandal with the issuance of Schengen visas by Polish foreign missions.

In response, the top Polish diplomat considered that "the latest statement by German Chancellor Olaf Scholz violates the principles of the sovereign equality of states, which is the foundation of good neighborly relations and friendly cooperation with Poland, as declared by the government of the Federal Republic of Germany in the 1991 Treaty with Poland."

The latest statement by German Chancellor Olaf Scholz violates the principles of the sovereign equality of states, which is the foundation of good neighbourly relations and friendly cooperation with Poland, as declared by the government of the Federal Republic of Germany in the…

— Zbigniew Rau (@RauZbigniew) September 24, 2023

"Statements in this regard indicate an attempt to interfere in the internal affairs of the Polish State and the ongoing electoral campaign in Poland," Rau said on X, formerly known as Twitter.

He also called on the German Chancellor to respect Poland's sovereignty and refrain from making statements that are detrimental to the relations of the two countries.

On Thursday, the European Commission said it had sent a letter to Poland seeking clarification over allegations that Polish authorities had long issued visas in exchange for bribes.

Polish media reports said a system for giving out visas to people from the Middle East and Africa in exchange for bribes had been put in place through the Polish consulates and some external companies in the countries concerned.

German Interior Minister Nancy Faeser called her Polish counterpart Mariusz Kaminski Tuesday, and her Ministry asked Warsaw's envoy to Berlin to appear over the issue, officials said.

During the talks, Berlin demanded that Warsaw provide "rapid and complete clarification" of the "serious" allegations.

The European Commission on Wednesday gave Warsaw two weeks to provide "clarifications" of the charges, calling the reports "very concerning".

Berlin's queries prompted an angry response from Kaminski, who rejected the "absurd" claims regarding the scope of the affair.

"Unfortunately, the German press latched onto the opposition's completely absurd narrative regarding the scale of what we were dealing with," Kaminski told Poland's Radio Zet.

"I spoke to the German interior minister yesterday... I explained the actual scale."

While the authorities in Warsaw say the scheme may have involved several hundred Polish work visas, the Polish opposition says the real number could be around 250,000.

Poland's secret service said last week that seven people had been detained in the scandal ahead of the October 15 elections, in which the governing party is running on an anti-immigration platform. Three of the seven are under arrest, according to the prosecutor's office.

Polish media have reported that the Foreign Ministry was involved in the scheme, which the opposition Civic Platform party has branded "the biggest scandal in Poland in the 21st century."

Deputy Foreign Minister Piotr Wawrzyk resigned over the affair last week, though the official reason for his departure was "absence of sufficient cooperation."

German Interior Ministry Spokesperson Mehmet Ata told reporters that Berlin was seeking information from Warsaw about how many visas were issued and when, as well as the nationalities of the recipients.

Warsaw had briefed Berlin on the ongoing investigation without providing further details, he added.

Germany's federal police had already tightened checks at the Polish border before the case erupted due to an increased influx of migrants.

The dispute with Poland comes against the backdrop of heightened tensions within the EU over the fair distribution of asylum seekers.

Berlin said last Friday it had stopped accepting migrants living in Italy under a European solidarity plan to send "a signal" to Rome.

On a visit to Italy on Wednesday, German President Frank-Walter Steinmeier told the daily Corriere della Serra that both Germany and Italy were "at their limits" when it comes to taking in migrants.

He said that it was now necessary to work "together and in a concentrated manner on humane and sustainable European solutions."

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