COVID-19 has ruled Johannes Høsflot Klæbo out of racing in Drammen ©Getty Images

Norway's Johannes Høsflot Klæbo has been forced out of tomorrow's one-day International Ski Federation (FIS) Cross-Country World Cup event in Drammen after contracting COVID-19, while women's leader Natalya Nepryaeva will not compete as Russian athletes are banned.

Klæbo's lead will be safe despite fears circulating that his season may be over after there was a coronavirus outbreak within the Norwegian squad.

"This is a trifle when we see what is happening around us," Klæbo said, as reported by Drammens Tidende.

"I have taken two quick tests which were both positive. 

"Now I'm on my way to Lillehammer to take a PCR test. 

"Then I get a final answer."

The five-time Olympic champion has 1,375 points from 19 events so far this season, giving him a healthy advantage over Russia's second-placed Alexander Bolshunov on 878 points.

Bolshunov cannot compete again this season after the FIS barred all athletes from Russia and Belarus.

Finland's Iivo Niskanen holds third place with 585 points after his win in Lahti last week.

The 30-year-old pipped Klæbo to gold in the 15 kilometres classical to prevent him recording a double after the Norwegian took victory in the sprint event the day before.

Lahti was the first World Cup event after the Beijing 2022 Olympic Games, where Klæbo was forced to miss out on the last race due to illness.

Nepryaeva will be unable to protect her lead in Drammen after organisers confirmed that Russian athletes would not be allowed to participate due to the country's invasion of Ukraine.

As a result of the attack, the FIS has also cancelled the remaining three races of the season scheduled for Tyumen in Russia.

This means that just four races are left on the calendar - in Drammen, Oslo and Falun in Sweden.

Nepryaeva has not won a World Cup event for two months and finished second to Norway's Therese Johaug on the second day of the Lahti stop.

The Beijing 2022 gold medallist has 973 points overall putting her in pole position in the women's table.

American Jessie Diggins and Swede Ebba Andersson make up the top three with 695 and 688 points, respectively.