Fears are growing for the future of the World Anti-Doping Agency amid concerns that the International Olympic Committee wants to neuter, sideline or even replace it as punishment for calling for a blanket ban on Russian athletes at the Rio Olympics.

At a Wada thinktank on Tuesday there were open discussions about how the IOC was considering establishing an “integrity unit” responsible for corruption, match-fixing and anti-doping in a move that could be used to erode Wada’s powers.

The organisation also came under a blistering attack from Gerardo Werthein, the Argentinian IOC member and president of the Argentinian Olympic Committee, who accused Wada of “letting down the sports movement” and attacking its “obvious efforts to blame major problems in the system on others”.

Werthein, an ally of the IOC president, Thomas Bach, also floated the idea of a “successor body” to Wada, which he said had failed in its duties.

“Despite the various inquiries which have been launched, we have still not had an adequate explanation on why Wada did not act earlier on the situation in Russia when they had been fully alerted to the doping problem as early as 2010,” he wrote on the Around the Rings website. “Indeed, Wada consistently declared the Russian national anti-doping agency code compliant and then re-accredited their Moscow lab just ahead of the 2014 Sochi Games.”

“Nor have we been provided with any serious analysis as to how Wada has let the sports movement and national governments spend major amounts of money on almost 300,000 tests per year and yet find so few of those who appear now to have been cheating. In truth most of the major doping cases have largely resulted from work by international federations, police investigations, whistle blowers and the media.”

But supporters of Wada believe that such attacks are a smokescreen to hide the real intention of the IOC – to punish its independent anti-doping body for being too independent when it came to punishing Russia over state-sponsored doping. They fear the IOC wants a more compliant anti-doping body that does not ruffle too many feathers or challenge its authority.

Wada came under a coordinated attack from IOC members in Rio before the Olympics over its calls for an outright ban on Russia in the wake of the state sponsoring doping revelations in Professor Richard McLaren’s report.

The former Wada president Dick Pound, who led an independent commission report that revealed details of widespread state-sponsored Russian doping last November, told the Guardian: “I’ve always thought the IOC’s attacks on Wada were a diversion to take everyone’s mind off how the whole Russian situation has been bungled. Wada did exactly what it was supposed to do – which is bring recommendations against Russia – but one of the stakeholders didn’t like them.”

Discussions on the future of anti-doping are expected to take place between the IOC, Wada and other stakeholders at a special Olympic summit on 8 October in Lausanne. Bach has called on IOC members to come forward with ideas.

Sir Craig Reedie, the Wada president who is also an IOC member and has come under fire from both sides, said he had repeatedly explained why Wada was not able to do more to tackle the Russian issue earlier and remains hopeful that the body will retain its clout and independence.

“I don’t think there is any incentive for the IOC to sideline Wada. The IOC doesn’t do any testing, apart from at an Olympic Games. The IOC has expressed a wish that there should be an independent testing unit and we are working on that this week,” Reedie told the Guardian. “We need to work out whether this should be under the Wada banner or whether it should be a separate organisation – who will make use of it and who will fund it.”

He said that if an independent testing unit was set up, then it would be difficult for Wada to run it without compromising its role as a regulator, though it could play a role in establishing it in the first place.

“If the IOC establishes its own integrity unit, I await information on how that will be structured. I think the IOC are well aware that the other stakeholders in Wada are governments,” Reedie added. “Inevitably the organisation would lose its independence, which is absolutely central to its functioning.”

The former Wada director general David Howman said recently that while he had long supported the idea of a more wide-ranging integrity unit, he was very concerned about the concept being advocated by some within the IOC.

“This concept of some kind of integrity unit is something I have talked about and supported for a long time, but not in the form the IOC are thought to be advocating,” the New Zealander told Inside the Games. “For them it seems to be about retaining control rather than ensuring full independence.”

Senior figures within the anti-doping movement are hoping that world governments, which collectively split the $30m annual budget for Wada 50-50 with the IOC, will put pressure on the IOC to maintain its independence. They believe the focus should be on strengthening Wada’s independence, improving its governance and increasing its funding.

Reedie, who has previously called for broadcasters and sponsors to invest in the fight against doping, said: “There are three challenges. Changes in the code are necessary to cover the kind of corruption we’ve faced. We need increasing powers to deal with non-compliance. And we need to look at our own governance and whether after 17 years the structure is still the right one.”

During a wide ranging debate about the future of anti-doping in the midst of the crisis sparked by systemic Russian cheating, serious issues in other parts of the world and whether Wada is fit for purpose, it has also been suggested that the IOC could turn to other organisations to fulfil its functions.

The IOC insisted that the ongoing process was designed to result in a more effective anti-doping system. “The IOC is calling for a more robust and efficient anti-doping system. This requires clear responsibilities, more transparency, more independence and better worldwide harmonisation,” said a spokesman.

“The IOC will continue its push to make doping testing and sanctioning independent from sports organisations.”

At the Wada thinktank on Tuesday, the investigative reporter Declan Hill gave a keynote speech warning that Wada’s future was also being threatened by negotiations with the IOC and the Qatari-funded organisation the International Centre for Sports Security (ICSS) about a proposed new agency to be called the Sports Integrity Global Alliance.

However Chris Eaton, the executive director of Sport Integrity at the ICSS, insisted that rumours of an IOC and ICSS collaboration were wide of the mark. “But I do believe we have got to be talking of this in a more selfless way,” he said. “There needs to be a discussion among all parties about how we preserve the credibility of sport.”