Germany is watching Iran's increasing military build-up with concern, because of its destabilizing activities in the region and drone deliveries to Russia, the Foreign Ministry said Wednesday.

The ministry also cited uranium enrichment in Fordow and the brutal repression of Iran's own population as other reasons for concern and said Germany was in close dialogue with partners in the region and within Europe as well as the United States on these developments.

Iran is increasing its stockpile of uranium enriched to 60 percent and in February news emerged that UN inspectors had found particles enriched to 84 percent.

Tehran has also delivered hundreds of kamikaze drones to Moscow to target Ukrainian infrastructure. The United States and European powers have warned the Islamic Republic to cease its intervention in Ukrainian war, as they have frozen nuclear talks with Tehran.

Iran designated two German diplomats as personae non gratae and is expelling them, foreign ministry spokesperson Nasser Kanaani said on Wednesday.

"The two German diplomats are being expelled due to their country's irresponsible interference in Iran's internal and judicial affairs," Kanaani said.

The US and its European allies have harshly criticized Tehran’s deadly crackdown on antigovernment protesters that killed 500 civilians and sent tens of thousands to jail.

The German foreign ministry said the expulsion was expected but "is arbitrary and unjustified.”

"They have done nothing wrong," the ministry added.

The move came after Germany expelled two employees of the Iranian embassy in Berlin last week in response to Iran sentencing a German national to death.