President Joe Biden responded to the Russian attack on Zaporizhzhia nuclear plant in Ukraine, which Ukrainian officials claim could have led to a disaster “10 times larger than Chernobyl.”

According to a statement from the White House, President Biden spoke with Ukrainian President Volodymyr Zelensky on Thursday evening to receive an update on the fire at the facility. Biden joined Zelensky in “urging Russia to cease its military activities in the area and allow firefighters and emergency responders to access the site.”