New Zealand Olympic administrators on Monday backed the International Olympic Committee's decision on allowing Russian athletes go compete at the Rio Games, but the country's official agency for monitoring doping in sport has voiced its disappointment.

The New Zealand Olympic Committee (NZOC) issued a statement confirming its support for the decision not accept the entry of any Russian athlete to the Rio Olympics unless they can prove without doubt to be clean.

The decision set a very high bar for Russian athletes to compete at Rio, it said.

"The impact of the Russian state-sanctioned doping program has been widespread and shocking and the IOC (International Olympic Committee) has taken the strongest possible measures," said the statement.

"The complexities of the matter cannot be understated and the New Zealand Olympic Committee is satisfied the IOC has considered the issues with the utmost care, balancing individual justice with collective responsibility."

However, the official anti-doping agency, Drug Free Sport New Zealand (DFSNZ), which last week backed calls for a total ban on Russian participation at the Rio Olympics and Paralympics, said the IOC's decision was "a black day" for clean athletes.

Making the international sports federations responsible for assessing whether athletes in their own codes should be allowed to participate showed a lack of will of the IOC to back its core principles with "hard decisions."

"We are extremely disappointed at the IOC's failure to show adequate leadership in protecting the integrity of sport," DFSNZ's chief executive Graeme Steel said in a statement.

"Many international federations will have neither the time nor capacity to make the quick and clear decisions necessary let alone do it in a consistent way," said Steel.

The IOC decision followed the McLaren Report from the World Anti-Doping Agency, which confirmed allegations of state-sponsored doping among Russia's elite athletes and of a cover-up of positive doping tests.

It requires Russian athletes to prove to their code's international federation that they meet international norms and to be tested outside of the Russian system.