Former Russian president Dmitry Medvedev has accused the German government of suppressing opposition voices amid controversy over a planned visit to Russia by several politicians from the far-right Alternative for Germany (AfD) party.

"I think that the Alternative for Germany as a political force - and by the way, a very significant one - is now under colossal pressure in Germany," the state news agency TASS cited Medvedev as saying on Friday.

He claimed that the current German coalition had "wet their pants" over the AfD's trip to Russia.

"Party comrade [Friedrich] Merz has decided that if they [the AfD members] go to Russia now, it would be very bad for his coalition," said Medvedev, who remains influential as the deputy chairman of the National Security Council in Russia.

Therefore, he said, the AfD was told it would be better not to go - and given their pressured situation, the party "had no other choice." However, he added that this was bad for German-Russian relations.

The trigger for his anger is the commotion over the planned trip by AfD Bundestag members Steffen Kotré and Rainer Rothfuss to the Russian Black Sea resort of Sochi for an international BRICS-Europe symposium.

After discontent was voiced within the party, Rothfuss cancelled his trip. Kotré, however, is believed to have landed in Russia along with AfD politicians Jörg Urban and Hans Neuhoff, according to media reports.

Medvedev threatened a nuclear strike against Berlin

Medvedev, who is appearing as a speaker in Sochi, is considered a hardliner in the inner circle around Russian President Vladimir Putin.

In Russia's war against Ukraine, he has called for the capture of the Black Sea port city of Odessa or the capital Kiev, and he has repeatedly threatened the West with nuclear strikes - including the German capital Berlin.