The outgoing Dutch prime minister, who has the support of all alliance members, Rutte is hotly tipped to become the next NATO chief after Jen Stoltenburg steps down in October.

Speaking to Polish broadcaster Radio ZET on Friday, Duda said: “Over recent years, I have heard him speak more than once about Russia, the war that Russia is fighting, about Russian crimes committed in Ukraine by Russian soldiers, about the responsibility of the Russian authorities for all this.

“Also, when we talked in Prague about aid for Ukraine and the Czech ammunition initiative.

“He knows what is going on, who is the aggressor.

“This, from the point of view of our interests, the security of Poland, is a fundamental issue, and looking at it from this point of view, I remain calm.”

The election for the new NATO Secretary General is expected to take place in the first half of July during the NATO summit in Washington.