One of the world's leading anti-doping experts has called on Olympic chiefs to ban Russia from the Rio Games across all sports if allegations of state-sponsored doping at Sochi 2014 are proven.

An independent commission, set up by the World Anti-Doping Agency (WADA) and chaired by Professor Richard McLaren, has been investigating those claims and its report will be published in Toronto on July 18.

United States Anti-Doping Agency (USADA) chief executive Travis Tygart told Press Association Sport that, if McLaren's report was as damning as expected, the entire Russian delegation should be prevented from taking part in the Games.

"If the claims about the 2014 Winter Olympics are true, we wholeheartedly agree with International Olympic Committee (IOC) president Thomas Bach that it's an unprecedented level of criminality and we think those behind this criminal enterprise should not be anywhere near the Olympics," said Tygart.

He said such dramatic action was needed as global sport was facing an integrity crisis.

McLaren has primarily been looking into claims made by the former director of the WADA-accredited laboratory in Moscow, Grigory Rodchenkov, that he doped dozens of athletes, including at least 15 medallists, in the build-up to the 2014 Winter Games held in the Russian resort of Sochi.

Rodchenkov told The New York Times in May that he did this in concert with the Ministry of Sport and that he also doped athletes before London 2012, the 2013 World Athletics Championships in Moscow and 2015 World Swimming Championships in Kazan.

Rodchenkov, who is now in hiding in the US, also claimed the Russian security service worked out how to open and re-seal the supposedly tamper-proof doping sample containers, and that he removed 100 Russian samples from the Olympic lab in Sochi through a hole in the wall at night.

Tygart, who built the case that brought down Lance Armstrong, said the IOC's own Olympic Charter made it clear that the Russian Olympic Committee could and should be held accountable if this is proven.

The comment he made about agreeing with Bach was a reference to a first-person piece the IOC president wrote for USA Today shortly after the Sochi allegations were first revealed.

The 62-year-old German described the "very detailed" claims as potentially representing a "shocking new dimension in doping", which he would respond to with his usual "zero tolerance policy".

The former Olympic fencing champion, however, has made these claims before, only to then focus on individual dopers as opposed to punishing state apparatus.

Tygart stopped short of criticising Bach directly but he pointed out that McLaren told athletics' world governing body the IAAF in June he had already found evidence the Moscow lab was manipulating samples between 2011 and 2013.

Rumours of doping in Russia have circulated for years but they began to become more concrete in 2014 when a German documentary broadcast allegations of a more organised approach within the country's track-and-field programme.

A WADA-funded panel spent the next 11 months investigating those claims and its explosive report in November 2015 resulted in the Russian anti-doping agency and main Moscow laboratory being shut down, and a suspension from global competition for Russia's athletics federation.

Last month, the IAAF voted unanimously to uphold that suspension and allow only those Russians completely untainted by the system to compete in Rio as "neutral athletes".

More than 90 Russians applied to the IAAF for Rio eligibility but only two were approved, although the Russian Olympic Committee is challenging this at the Court of Arbitration for Sport.

But, with McLaren's report arriving before that tribunal concludes on July 21, there is a very real prospect that athletes and officials from around the world will be demanding the same treatment for the entire Olympic team, which would mean no Russian anthem, kit or flag and only a small band of foreign-based athletes with spotless anti-doping records, competing under the Olympic flag.