Vitaly Milonov, of the United Russia party, accused the UK of being behind a “fantasy” operation involving the poisoning of former double agent Sergei Skripal and his daughter Yulia.
The Russian MP branded the incident “fake news”, saying it was nothing to do with Moscow.
Mr Milonov told the BBC: “My personal point of view (is) that Theresa May and her colleagues they have created a fake story because they need an explanation to British people and British business why they are going to perform some anti-British steps in favour of United States policy against Russia.
“So, they had to make this fantasy. They had to kill, to try to kill, this poor pensioner, useless for us.
“This is a drama for British TV. It’s a behaviour of Hitler when he blamed someone in burning of Reichstag.”
Mr Milonov also branded Mr Skripal a “useless fake agent”.
Asked how the nerve agent came to Britain, Mr Milonov said: “This poison is 50 years old, it’s not modern stuff. You can take this poison from any laboratory in Ukraine or other fake countries that are happy to help you.”
The Russian MP compared the situation to being like a James Bond movie, saying: “You created such a horror about new Russia which is very dangerous. For us this guy is absolutely useless.