Russia has dispatched one of six giant magnets that will be used for the ITER nuclear fusion programme in France, one of the last international scientific projects Moscow is still participating in amid tensions over its war in Ukraine.
The ship carrying the Russian-made magnet, or "poloidal field coil", departed Saint Petersburg under grey skies on Tuesday.
The 200-tonne, nine-metre-wide coil had been tightly wrapped to withstand the two-week trip to Marseille in the south of France.
The ring-shaped magnet was built under the supervision of Russia’s atomic agency Rosatom and will make up the top part of the world's largest "tokamak".
The tokamak is a magnetic fusion device built in France following the same principle that powers our sun and stars.
The Russian component was originally scheduled for shipping in May, but sanctions forbidding Russian ships from docking in Europe delayed the departure.
Still, the "current situation did not change the fact that we will fulfil our obligations”, Rosatom representative for international projects, Viacheslav Perchukov, said.
Geopolitical tensions "practically did not affect the realisation of this project," Perchukov added.
"Without (the Russian coil), the tokamak will not work," senior ITER centre scientist Leonid Khimchenko told AFP.
He hailed a "unique" achievement which has been over eight years in the making.
In southern France, 35 nations are collaborating to build the largest nuclear fusion device in the world.
"This is such an interesting project that, in fact, we are all one family... there is no competition between us, nothing," Khimchenko said.
The project was set in motion after a 1985 summit between then US President Ronald Reagan and Soviet Union leader Mikhail Gorbachev.
Andrey Mednikov, a scientist in charge of the production of the poloidal field coil, praised the continuing international cooperation.
"If this cooperation was brought to a halt," Mednikov said, "everyone would lose: both Russia and the international community".
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