Russell Brand has denied unspecified “very, very serious criminal allegations” he said had been put to him by a television company and newspaper.

The former actor and broadcaster, 48, posted a video to his YouTube channel today addressing claims he said had been made about him in private letters by journalists.

Brand said he had received “two extremely disturbing letters” detailing “a litany of extremely egregious and aggressive attacks” from a “mainstream media TV company and a newspaper”.

He denied what he said were “astonishing” and “rather baroque” claims of a “serious nature”.

“These allegations pertain to the time when I was working in the mainstream, when I was in the newspapers all the time, when I was in the movies,” he said.

“As I’ve written about extensively in my books, I was very, very promiscuous. Now, during that time of promiscuity, the relationships I had were absolutely always consensual.”

The exact allegations that had been put to him by the unnamed broadcaster and newspaper were not clear from the video, which was also uploaded to his Twitter account.

But Brand accused the outlets of having a “serious and concerted agenda” to silence him, adding: “I feel like I’m being attacked.”

Since ending his career as a stand-up comedian and presenter, including for the BBC, Brand has written a series of political and self-help books.

He has also launched a podcast, Stay Free With Russell Brand, which discusses “revolutionary politics and spiritual awakening”.

He currently runs a mental health and yoga-themed YouTube channel named Awakening with Russell.

Brand: ‘I feel like I’m being attacked’

In the video, posted to the same channel today, Brand said it wasn’t “the usual type of video we make on this channel, where we critique, attack and undermine the news […] because in this story, I am the news”.

“I’ve received two extremely disturbing letters, or a letter and an email, one from a mainstream media TV company, one from a newspaper, listing a litany of extremely egregious and aggressive attacks, as well as some pretty stupid stuff, like my community festival should be stopped, that I shouldn’t be able to attack mainstream media narratives on this channel,” he said.

“But amidst this litany of astonishing, rather baroque attacks, are some very serious allegations that I absolutely refute.

“These allegations pertain to the time when I was working in the mainstream, when I was in the newspapers all the time, when I was in the movies.”

“As I’ve written about extensively in my books, I was very, very promiscuous. Now, during that time of promiscuity, the relationships I had were absolutely always consensual.

“I was always transparent about that then – almost too transparent. And I’m being transparent about it now as well.

“And to see that transparency metastasised into something criminal, that I absolutely deny, makes me question: is there another agenda at play?”

He went on to accuse the media outlets of a “co-ordinated attack”.

“I’m aware of news media making phone calls, sending letters to people I know, for ages and ages,” he said.

“It’s been clear to me, or at least it feels to me, like there’s a serious and concerted agenda to control these kinds of spaces and these kinds of voices – and I mean my voice along with your voice.”

Without listing the allegations against him, Brand added: “It’s worth mentioning that there are witnesses whose evidence directly contradicts the narratives that these two mainstream media outlets are trying to construct, apparently in what seems to me to be a co-ordinated attack.”

“Now, I don’t want to get into this any further because of the serious nature of the allegations, but I feel like I’m being attacked and plainly they are working very closely together.

“We are obviously going to look into this matter, because it’s very, very serious.”