Webster, one of the most popular British weightlifters in recent years, twice refused offers from UK Anti-Doping to halve the ban by admitting that he knowingly took the drug, which is used to treat osteoporosis and muscle wastage.

He said he did not suffer from either of those conditions, and although he suspected cross-contamination of legal substances, or hydration tablets, as the source, he did not know how the ostarine got into his body.

Since his suspension was imposed, New Zealand news website Stuff reports that Webster has made a living holding weightlifting coaching seminars around the world.

He has mainly been targeting the crossfit community.

Webster's roadshow is scheduled to arrive in New Zealand next month, with tickets, advertised at a price of NZD$250 (£128/$164/€144), on sale for seminars in Auckland on December 8, Wellington on December 9 and Queenstown on December 16.

But Olympic Weightlifting New Zealand has sent out a notice to all its members threatening athletes of all levels that they could be suspended if they attend any of the seminars.

The notice states that members are bound by the Sports Anti-Doping Rules (SADR), which aim to prevent athletes from associating in a professional or sport-related capacity with a coach or support person who is serving a ban for doping.

In order for SADR to apply, anti-doping authorities must inform athletes in advance of the support person's disqualifying status and the potential consequence of associating with them.

Athletes’ responsibilities under SADR were explained in a more detailed letter from Drug Free Sport New Zealand (DFSNZ), which was attached to the notice.

"DFSNZ has become aware that Sonny Webster will be in New Zealand in December 2018 offering coaching seminars," the letter, signed by DFSNZ's testing and investigations programme director Jude Ellis, reads.

"The seminars will potentially cover aspects of weightlifting.

"His ban prohibits him from participating in sport in any capacity, which includes coaching athletes who are bound to [New Zealand's Sports Anti-Doping Rules].

"This letter notifies you that you are prohibited from associating in any professional capacity with Mr Sonny Webster.

"Having now received this notice, should you breach this rule, you would be committing an anti-doping rule violation and could be banned from sport for up to two years."

In an interview with insidethegames shortly after his ban was confirmed, Webster said he has spent his life savings in an unsuccessful attempt to prove his innocence by establishing the source of the ostarine.

"My integrity is worth far more than any amount of money," the 94 kilograms lifter said.

Webster’s best performance came in 2016, when he totalled 346 kilograms at the British Championships.

He finished fifth at the Glasgow 2014 Commonwealth Games and 14th at the Rio 2016 Olympic Games, where he was Britain’s only male weightlifter. 

Webster’s suspension, which having been backdated is due to end at midnight on June 13, 2021, was not announced earlier than last December because he had been going through an appeals process.