Dmitry Kiselyov said on his Sunday night news show the choice of car proved the "English” were the mastermind of the killing, adding the Mini Cooper was a “weakness of theirs”.
Ms Dugina, the 29-year-old daughter of the philosopher, writer and political theorist described by some in the West as Russian president Vladimir Putin’s “brain”, died when an explosive planted in her car exploded as she was driving.
Russia’s Federal Security Service (FSB), the main KGB successor agency, has claimed Ms Dugina’s killing was “prepared and perpetrated by the Ukrainian special services”.
A Ukrainian woman, Natalya Vovk, has been accused of her murder. According to the FSB's case file, Ms Vovk entered Russia driving a Mini Cooper, accompanied by her 12-year-old daughter.
It has been claimed Mr Dugin, rather than his daughter, could have been the target of the attack.
Mr Kiselyov said for the West, a terror attack on Mr Dugin “was supposed to create the biggest splash”.
"‘How on earth did they blow up Putin’s brain?’,” he said, speaking of the hypothetical killing of Mr Dugin. “For the West, it would have been major.
"I’m saying that because the main interested parties are clearly not in Ukraine. The West's well-honed signature is all over this murder. From the crime’s thorough planning and the organisation of the border crossing, to the selection of the perpetrator. Who would suspect a mother with her daughter? To the scrupulous fabrication of documents to go with the interchangeable number plates.”
He pointed to assassinations carried out by the US such as those of al-Qaeda leader Osama bin Laden and Iranian Iranian military officer Quasem Soliemani, which he said had required the signature of US presidents.
"And most likely, it wasn’t the Americans, but the English,” he said. “In the US, for eliminating a person in this manner, they need a lot of signatures from the very top.”
He added: "The British operate more quietly, without gathering signatures. And they also love their cars. For example, the Mini Cooper is a weakness of theirs.”
Ms Vovk has been accused of perpetrating the killing and then fleeing from Russia to Estonia. The FSB has claimed Ms Vovk arrived in Russia in July with her 12-year-old daughter and rented an apartment in the building where Ms Dugina lived to shadow her.
It said Ms Vovk and her daughter had attended a nationalist festival, which Mr Dugin and his daughter were also at just before the killing. The agency said Ms Vovk and her daughter left for Estonia after Ms Dugina’s death, using a different license plate on their way out of the country.
Although the Mini Cooper was a British designed car when it was first released in the 1950s, it is now owned by German car maker BMW. The car was showcased as a British icon in 1969 film The Italian Job, which included Michael Caine's famous line: "You're only supposed to blow the bloody doors off."
In 2013, Mr Kiselyov was appointed by Mr Putin to head Rossiya Segodnya, a Russian state-controlled media group.