USA Weightlifting (USAW) also wants retests carried out, before this year's Olympic Games in Tokyo, on stored weightlifters' samples held by both the International Olympic Committee (IOC) from Rio 2016, and the International Weightlifting Federation (IWF) from recent World Championships and other events.

The IOC admitted accusations made in Secret Doping - the Lord of the Lifters by the German state broadcaster ARD were "very serious and worrying".

There were claims of doping cover-ups and financial mismanagement by the IWF, which it has strenuously denied, and revelations of children taking steroids in Thailand, where weightlifting is the most successful Olympic sport.

The Thai Amateur Weightlifting Association (TAWA) rejected the allegations made against it in the documentary and complained that an undercover journalist had posed as a weightlifting team manager.

Maxim Agapitov, President of the Russian Weightlifting Federation, said there should be "a truly independent, full-scale investigation" after ARD focused much of its investigation on Tamás Aján, President of the IWF, which is registered in Switzerland and has offices in Hungary.

While the IWF has denied allegations of financial malpractice – it was claimed that millions of dollars were placed in two Swiss bank accounts accessible only by Aján – the IOC said it had asked for files from the programme makers "in order to properly address" the accusation.

Phil Andrews, chief executive of USAW, said: "The critical thing is to really investigate the allegations and take relevant action against those found guilty, regardless of who they are."

Andrews revealed USAW was calling on the IWF "to explain the allegations regarding the management of finances of the Federation" and that he "would expect anyone who is found to have been involved in the incidents mentioned in the ARD documentary to be heavily sanctioned".

Many of the revelations in the documentary concerned incidents from four to 12 years ago and Andrews made the point that the IWF had "made significant strides forward in the rehabilitation of the sport" since 2017.

Weightlifting had been in danger of losing its Olympic status because of its doping problems, but after a series of reforms it was formally given the all-clear for future Games by the IOC in May.

Andrews highlighted improvements in an anti-doping-focused Olympic qualifying system, a clampdown on athletes who failed to let testers know their whereabouts, a new partnership with the International Testing Agency (ITA) and a commitment to education.

But he said: "This documentary proves the work can never stop – as we haven't stopped in the United States since changing our culture from the 1990s to today."

Agapitov sent to insidethegames a copy of a letter he wrote five weeks ago, asking Aján – the 80-year-old Hungarian who was general secretary of the IWF for 24 years before becoming President in 2000 – to add items to the agenda of a meeting of the IWF Executive Board.

Russian weightlifting has had a bad record in doping historically, before Agapitov's administration, and was banned from the 2016 Olympic Games in Rio de Janeiro.

It can send only two athletes, compared to the maximum of eight, to Tokyo 2020 because of multiple offences several years ago.

Agapitov, a former world champion who has overseen significant changes in his own Federation since taking over in 2016, wanted separate audits, by independent bodies, of the IWF's role in doping, IWF finances and taxes, and IWF governance.

He stipulated that Aján should be recused from all the investigating bodies because of conflict of interest.

Agapitov also queried the IWF's anti-doping policies and proposed reforms, and asked the IWF to explain how its testing procedures had missed "more than 50 athletes exposed by 2008 and 2012 Olympic retests".

He argued for more transparency, and posed questions about the role of the IWF director general, Attila Adamfi. 

Agapitov claimed the role was created in 2014 for Adamfi, Aján son-in-law.

"My proposals were completely rejected, without a real explanation," said Agapitov.

Questions about anti-doping procedures, finance and nepotism were raised in the ARD documentary, a full report of which appeared on insidethegames here.

The programme also suggested there had been questionable practices by officers of the Hungarian National Anti-Doping Agency (HUNADO), which carried out 77 per cent of 16,000 tests studied by ARD’s investigators.

HUNADO strongly denied any malpractice and said it was responsible only for collecting samples, leaving results management to the IWF.

Andrews said: "We strongly recommend the ITA [which, since four months ago, oversees IWF anti-doping procedures] engage with alternative testing agencies while any investigation is ongoing."

As a further precaution, Andrews said USAW wanted the IOC and IWF to retest "all held samples, using the latest technology, for those most likely to appear in the 2020 Olympic Games".

He said: "The 2020 Olympic qualification system allows for it to be clear who is likely to go to the Olympic Games.

"The allegations raised by Thai lifter show that it's likely there are still tested athletes with samples on hand that may have cheated our sport.

"Similarly, we applaud the increased testing of athletes from the IWF.

"Ahead of the Olympic Games, the IOC and the IWF must engage in an aggressive testing programme equally across the world."

Meanwhile, TAWA has rejected the documentary’s claims about doping in Thailand, where an undercover team recorded interviews with Siripuch Gulnoi, a bronze medallist at London 2012.

A TAWA statement said Gulnoi had complained to police about being duped by a reporter who claimed to be a German team manager, and, despite the interview being recorded and broadcast in the documentary, Gulnoi denied having said that girls as young as 13 take steroids, or that she herself had doped as a teenager.