John McAfee, the cybersecurity tycoon-turned-cryptocurrency backer said Tuesday that he will end his work on initial coin offerings (ICOs).

In a tweet, McAfee cited "SEC threats" when revealing that he would stop working on token sales or recommend them to his 800,000-plus followers on Twitter.

It represents the end of what was reportedly a notable line of business, with McAfee revealing in April that his ICO team was charging more than $100,000 for a single promotional tweet, according to a report from The Verge.

McAfee's statement follows a period of sustained criticism against the Securities and Exchange Commission (SEC), the U.S. securities market regulator that has steadily increased its oversight – and activity – in the crypto space since it said last summer that American securities laws may apply to some token sales.

It also comes just days after a senior SEC official said that ether – the cryptocurrency of the ethereum network – isn't a security, which largely came as a relief to members of the crypto community.

Just last week, for example, McAfee declared via Twitter that he would not accept the SEC's view that many token sales qualify as securities offerings. Indeed, earlier this month, McAfee challenged SEC chairman Jay Clayton to a public debate, posting what he claimed was the agency chief's phone number and encouraging his followers to make contact.

Plans to cease promoting ICOs aside, McAfee indicated that he isn't walking away entirely.

McAfee wrote that he was drawing up "an equivalent alternative to ICOs" which he said "the SEC cannot touch."

"Please have Patience," he concluded.

The SEC declined to comment when reached.

Image via Gage Skidmore/Flickr