"Are the United Nations really united if they can't make a common decision [...] and if one influential player has its own rules, shuffles the cards, sweeps the chess pieces off the board and says, stop it, this game doesn't exist," he told a press conference.
Landsbergis is taking part in an international conference on "Criminal responsibility for aggression against Ukraine. How to deliver justice?", held in the Lithuanian capital to discuss how to ensure that the leaders of Russia and Belarus, Vladimir Putin and Alexander Lukashenko, are held individually criminally responsible for war crimes in Ukraine.
"There are two types of justice: one of normal states and the other of ogres," he said. "The ogres are blocking a common understanding of justice."
Lithuania's former leader also said that in the face of the war in Ukraine, China's choice "whether it is in the family of normal states or part of the madhouse" will be important.
"There should be two UN organizations, one of normal nations and the other of madmen or cannibals. Let the cannibals meet in a separate room and decide whether they will have a common boss and whether that boss will be in Moscow or in Beijing," he said.
"Or maybe Beijing will not want to be in that room of cannibals? Let Putin sit alone then. We must forget that Russia is an allegedly normal state; there is no such Russia."
Landsbergis noted that Beijing "avoids [answering the question] for now" as "China, as usual, has a lot of time".
After Russia launched its military invasion of Ukraine, Lithuania initiated an appeal to the Hague Tribunal's prosecutor to open an investigation into war crimes and crimes against humanity committed by Russia and Belarus.
Lithuania became the first country to initiate the Hague Process under the Rome Statute establishing the International Criminal Court. The initiative has been joined by other countries in Europe and worldwide.
The Lithuanian Prosecutor General's Office has opened a pre-trial investigation into an alleged crime of aggression committed by the Russian and Belarusian regimes against Ukraine.
The Justice Ministry also proposes to establish a special tribunal in the European Union to ensure that the Russian and Belarusian leaders are held criminally responsible for the aggression in Ukraine.