Marine rescue group Sea Shepherd said a "major, complex operation will be undertaken that is not without risk" to save the whale from the Seine river, northwest of Paris.
Images show the emaciated sea mammal swimming slowly northwest of the French capital, and experts say it likely stopped eating before it entered the river.
French authorities were on Saturday preparing to give vitamins to a beluga whale that has swum way up the Seine river, as they race to save the malnourished creature, which has so far refused food.
The visibly underweight whale was on Tuesday first spotted in the river that flows through Paris to the English Channel.
On Saturday, it had made its way to about 70km north of the French capital.
“It’s quite emaciated and seems to be having trouble eating,” Isabelle Dorliat-Pouzet, a senior police official from the Eure department in Normandy, which is overseeing the rescue operation, told journalists.
Rescuers had tried
Members of conservation NGO Sea Shepherd went out on the river Seine in a motor boat to monitor the lost beluga whale s position, but the group s chief in. 05.08.2022, Sputnik International