Why Germany was key to prisoner swap deal with Russia

The German government's decision to release a convicted Russian killer serving a life sentence for murdering an exiled Chechen in Berlin in 2019 was crucial for the prisoner swap between Russia and the West.

source https://www.dw.com/en/why-germany-was-key-to-prisoner-swap-deal-with-russia/a-69835093?maca=en-rss-en-ger-1023-rdf