Sir Craig Reedie, the president of the World Anti-Doping Agency, has responded to a barrage of criticism from fellow International Olympic Committee members by saying he did not think all of them fully understood the agency's role.

The 75-year-old Scot listened as several IOC members blamed WADA for the Russian doping crisis, while Russia's Alexander Zhukov accused it of being part of a politically-motivated campaign to discredit the world's largest country.

Italy's Mario Pescante even suggested WADA had been "more interested in publicity and self-promotion than doing its job to ensure clean sport".

"I don't feel I've been thrown under the bus - I think we've made a reasonable contribution to the debate," Reedie told journalists later.

"(But) I think there's a lack of understanding of what WADA is all about.

"It's not often sport is confronted with what has come out about Russia in the last 18 months, so I think it's difficult for everyone to handle.

"It puts pressure on the IOC, it puts pressure on the athletes, so it's a natural reaction to point the finger."

Reedie continued by denying WADA was motivated by politics and said Pescante had later apologised for what Reedie described as a "personally offensive" remark.

He said he was "encouraged" by IOC president Thomas Bach's support and said there was now acceptance at the "very highest level in Russia" of the need to change.

He also highlighted the acknowledgement from some IOC members that WADA needed more money - 10 times as much according to Belgium's Pierre-Olivier Beckers.

"As far as money goes, it's hard to say how much would be enough," said Reedie of hints his organisation's £22.5m annual budget could be increased.

"I do know that we have a limited number of people employed around the world and every year we're asked to do more and more with the same resources."

But Reedie also admitted that "parts" of the system were broken and that the anti-doping community and Olympic movement needed to come up with a better response to the level of criminality recently uncovered by Canadian law professor Richard McLaren's report into cheating at the 2014 Sochi Olympics and other major events.

The limitations of WADA's arsenal of sanctions were highlighted by long-standing IOC member Princess Anne, who questioned the limitations for punishment of state-organised cheating. Hers was a rare voice of sympathy for Reedie's plight during a heated debate on the first day at the IOC's 129th session in Rio, as the Olympic family continued to struggle with the aftershocks of the seismic revelations about Russia's state-directed doping programme.

WADA's response to McLaren's investigation had been to ask the IOC to ban the Russian Olympic Committee - a request the IOC ignored, opting instead to let the sports decide which Russian athletes should compete, subject to IOC approval.

That final consent will come from a three-person panel comprised of Claudia Bokel, the outgoing head of the IOC's athletes' commission, World Archery president Ugur Erderner and the boss of the modern pentathlon federation Juan Antonio Samaranch Jr.

All three were absent from the afternoon programme and IOC spokesman Mark Adams later acknowledged they have started to vet the more than 250 Russian athletes in Rio, all of whom have already been cleared by the various sports federations and rubber-stamped by a Court of Arbitration for Sport arbitrator.