BERLIN - The Russian opposition, forced into exile and weakened by internal conflicts, will organise its first major demonstration against Moscow’s Ukraine invasion in Berlin on Sunday, testing its political credibility in the third year of the war. The Kremlin has in recent years eradicated any political competition at home and waged a massive crackdown on dissent, with hundreds -- possibly thousands -- of Russians in prison for their political views. With Vladimir Putin in power for almost 25 years, all of his political opponents are now dead, in prison or in exile. The Russian opposition lost its main figurehead in February, when Putin’s rival Alexei Navalny died in an Arctic prison in mysterious circumstances. Yulia Navalnaya, his widow who took the helm of the movement, is one of the main organisers of the march. Unable to operate at home, the opposition is forced to relaunch abroad, where hundreds of thousands of Russians fled in the aftermath of the February 2022 invasion. Berlin -- home to thousands of anti-Putin Russians and Ukrainian refugees -- was chosen as the prime location for the march. The protest is due to kick off at 1300 GMT in the German capital’s centre and will end outside the Russian embassy. Navalnaya is joining forces with two other oppositionists for the rally: former Moscow city councillor and longtime anti-Putin campaigner Ilya Yashin and Vladimir Kara-Murza, who survived two poisoning attempts. Both Yashin and Kara-Murza were freed from prison -- where they served sentences for denouncing the Ukraine invasion -- after a prisoner swap with the West this summer. “The march aims to unite everyone who stands against Vladimir Putin’s aggressive war in Ukraine and political repressions in Russia,” organisers said in a statement.