The Russian skater Kamila Valieva, who was only 15 when she found herself at the heart of a doping scandal at the 2022 Winter Olympics, has been banned for four years. The verdict means that Russia is certain to be stripped of its team gold from the Games, with the International Skating Union expected to formally announce on Tuesday that the medal will go to the United States.

Valieva’s ban was confirmed by the court of arbitration for sport, which said that the skater, now 17, would be stripped of all her results, prizes, medals and awards going back to Christmas Day in 2021 when she failed a test for trimetazidine (TMZ), a drug designed to prevent angina.

The verdict was immediately welcomed by the World Anti-Doping Agency, which condemned Valieva’s doctors and coaches in the strongest possible terms. “The doping of children is unforgivable,” it said. “Doctors, coaches or other support personnel who are found to have provided performance-enhancing substances to minors should face the full force of the World Anti-Doping Code.”

However in Russia the mood was one of resigned outrage. “Of course, we don’t agree with this,” Dmitry Peskov, Vladimir Putin’s press secretary, told reporters. “From my point of view, of course, it’s politicised.”

Meanwhile the distinguished Soviet coach Tatyana Tarasova was more blunt about Cas’s verdict. “Damn them! Scum!” she told championat.ru.

Valieva was billed as one of the stars of the 2022 Games and she initially delivered by becoming the first woman to complete a quadruple jump at the Olympic team event, as the Russian Olympic Committee won gold. But a day later it emerged that she had tested positive for TMZ six weeks earlier and a media storm broke out.

That was partly due to Valieva’s age and the question over whether a minor should face the same sanctions as an adult for doping. Lurking in the background was Russia’s past: the extent of the country’s state-sponsored doping meant that it was not allowed to show its flag or hear its anthem at the Games.

Eventually she was allowed to compete in the individual figure skating event by Cas. But, under the most severe pressure, she fell twice and finished fourth. There then followed two years of legal argument before Cas finally reached its verdict.

The verdict was also welcomed by the US Anti-Doping Agency chief executive, Travis Tygart, who said: “Today’s decision in the Valieva case has been a long time coming. It’s imperative that the ISU immediately handles the technical processes needed to reallocate the medals accordingly.

“As we know, Russia has hijacked the Games since 2014 where it was caught red-handed running a state-sponsored doping scheme that robbed clean athletes around the world,” he added. “Here, yet again, those entrusted to protect the Games and athletes have allowed Russia to jeopardise the wellbeing of its own athletes while robbing clean athletes and fans of an honest, fair, and authentic Olympic competition.”

Meanwhile the US Olympic Committee hailed the news as a “significant win not only for Team USA athletes but also for athletes worldwide who practice fair play and advocate for clean sport”.

“The incredible athletes of Team USA have displayed remarkable fortitude,” it added. “Their outstanding performances in Beijing will forever symbolize their commitment to clean competition.”