After German Chancellor Olaf Scholz decided to send Leopard 2 battle tanks to Ukraine last week following a long hesitation, the response from the Russian government was swift.

"Everything the alliance and the capitals of Europe and the United States do is perceived in Moscow as direct involvement in the conflict," Kremlin spokesman Dmitry Peskov said on Thursday, according to a report by the Russian news agency Interfax.

That's exactly what Scholz has been trying to avoid: triggering an accusation from Moscow that Germany is now also a direct party to the war in Ukraine. Speaking with public broadcaster ZDF on Wednesday, he rejected any interpretation that Germany is directly involved in a war with Russia. "No, absolutely not!" he said. "There must be no war between Russia and NATO."

But concerns linger that Germany's arms deliveries to Ukraine and the training of Ukrainian soldiers may make it a legitimate target of Russian attacks.

The legal concept of a "warring party" originates from the international law of the 19th and early 20th centuries. Becoming a party to a conflict hinges either on a formal declaration of war, or direct participation in specific combat operations.

Putting boots on the ground would make Germany a warring party, and providing intelligence for military operations or battle training for soldiers is considered a gray area. But weapons deliveries are seen as unproblematic.

All countries have the right to defend themselves

The United Nations Charter states: "All Members shall refrain in their international relations from the threat or use of force against the territorial integrity or political independence of any state, or in any other manner inconsistent with the Purposes of the United Nations."

Russia violated that precept with its attack on Ukraine last February. And the charter clearly provides that in this case, all countries have the right to defend themselves, individually or collectively.

German experts claim Russia is the only party violating international law. "Every shot that Russia currently fires in Ukraine is a continuation of the breach of international law," Markus Krajewski, professor of public international law at Erlangen-Nuremberg University, told public broadcaster ARD. "Russia will only behave in accordance with international law again when it withdraws its troops behind its own borders."

German Foreign Minister ruffling feathers

But more crucial than any legal definition is surely how Russian President Vladimir Putin will choose to interpret the weapons deliveries — and how he might react.

Just how sensitive the situation is right now was shown by the discussion that erupted following statements made by German Foreign Minister Annalena Baerbock, of the Green Party.

During a meeting in Strasbourg last week, she called for cohesion among Western allies by saying: "We are fighting a war against Russia and not against each other." Her choice of words caused a stir, as politicians from Western countries have been careful to emphasize so far that supporting Ukraine does not mean they are a party to the war.

Russian Foreign Ministry spokeswoman Maria Zakharova demanded an explanation from the German ambassador in Moscow on Friday about the "contradictory" statements from Berlin. On the one hand, she said, Germany has declared that it is not a party to the conflict in Ukraine, while on the other hand Baerbock had said the countries of Europe were at war with Russia.

"Do they themselves understand what they are talking about?" wrote Zakharova on the Telegram messenger channel.

Even if Germany and its Western allies are on the safe side as far as international law is concerned, they are now increasingly becoming the focus of Russian propaganda as a result of the deliveries of heavy weapons. Putin has shown little concern for  international law in the past, and he is unlikely to do so in the future.

This article was originally written in German.

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