Sebastian Vettel and Max Verstappen have called on Russia to be removed from the Formula 1 calendar as fury mounts over the invasion of Ukraine.
Vettel said he will not race at the Russian Grand Prix in Sochi, scheduled for September 25, if it takes place as planned.
F1 said in a statement they were "closely watching the very fluid developments", while Istanbul has reportedly emerged as a potential replacement on the calendar.
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"My own opinion is I should not go, I will not go. It's wrong to race in the country,” said Vettel at pre-season testing in Barcelona.
“I'm sorry for the people, innocent people who are losing their lives, getting killed for stupid reasons."
World champion Verstappen also added his thoughts, saying: "When a country is at war, it is not right to race there."
The F1 statement added: "We will continue to monitor the situation very closely".
Sporting bodies are under pressure to scrap events in Russia due to the country's large-scale military attack on Ukraine.
The Champions League final is reportedly set to be moved from St Petersburg after UEFA called an extraordinary meeting of its executive committee.
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