"He is the devil incarnate. An absolute madman. And whatever he wrote or said, it cannot be called anything but the ravings of a madman," Putin's spokesperson Dmitry Peskov told Kommersant newspaper, referring to Anders Behring Breivik.
The 32-year-old, who has admitted carrying out twin bombing and shooting attacks on Friday, penned a 1 500-page manifesto in which he urges an end to what he describes as a centuries-long Muslim colonisation of Europe and speaks of his admiration for Putin.
In the manifesto, he also denounces political correctness and speaks of the need to establish a Norwegian equivalent of Russia's pro-Putin Nashi patriotic movement.
The Moscow-based movement immediately sought to condemn the mass-killer's philosophy, calling him a "psychopath and fascist".
"Regardless of the topic he speaks on, the opinion of Anders Breivik remains an opinion of a madman," Nashi spokesperson Kristina Potupchik told state news agency RIA Novosti.
"Breivik pursued the goal of destabilising the situation in Norway and drawing attention to his fascist ideas. The Nashi movement is known for its uncompromising fight against Fascism and we believe we should not react to statements by psychopaths and fascists."
Nashi (Ours) is one of a handful of youth groups which emerged during Putin's 2000-2008 presidency. It professes vehement support for the Kremlin and is known for public harassment of opposition politicians and Western diplomats.
After the tragedy Putin called the Norwegian Prime Minister Jens Stoltenberg and also sent him a telegram of condolence to condemn the "barbaric crimes".
- Click here to read an excerpt of a Q&A in which Breivik interviews himself as part of his 1 500-page manifesto.