HAVANA -- Former Cuban President Fidel Castro has jumped to the defense of Russia, comparing the new NATO chief to the Islamic State of Iraq and Syria (ISIS) in an article penned Monday evening.

Reacting to statements made Sunday by the new NATO secretary-general, former Norwegian Prime Minister Jens Stoltenberg, Castro wrote: "How much hate in the face! What an incredible determination to promote a war of extermination against the Russian Federation!"

Stoltenberg spoke in Poland saying the Western alliance could deploy its forces wherever it wants. His statements were generally seen as a reaction to Russia's recent behavior in Crimea and Ukraine and as intended to reassure Poland, a NATO member, that it would be protected in the event of any Russian moves against it.

New North Atlantic Treaty Organization (NATO) Secretary General Jens Stoltenberg of Norway speaks at his first press conference at the NATO headquarters in Brussels on October 1, 2014. THIERRY CHARLIER/AFP/Getty Images

Castro, however, described the NATO chief's remarks as fanaticism comparable to that of ISIS.

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"Who turns out to be more extremist than the very fanatics of the Islamic State?" he wrote in the article published by the Cuban media Tuesday. "What religion do they practice? After this, is it possible to enjoy eternal life on the right side of the Lord?"

Although a NATO summit a month ago turned down appeals from Eastern European NATO members to station thousands of troops there permanently, Stoltenberg, who as Castro points out became NATO chief just six days ago, appeared to take a harder line in Poland.

"Next year, at the ministerial meeting, we will take decisions regarding the so-called spearhead but, even before it is established, NATO has a strong army after all," he told the local state broadcaster TVP Info. "We can deploy it wherever we want to."

Stoltenberg added, "These capabilities already exist. We have them, and we can deploy them in individual regions. And this is only an add-on to what the alliance already has."

In his article, Castro also weighed in on the evolution of man, the latest discoveries about black holes by University of North Carolina professor Laura Mersini-Houghton and the work of British scientist Stephen Hawking.