Cuba has uncovered a human trafficking ring that has coerced its citizens to fight for Russia in the war in Ukraine, its foreign ministry said, adding that Cuban authorities were working to "neutralize and dismantle" the network.

The statement from Cuba's foreign ministry gave few details, but noted the trafficking ring was operating both within the Caribbean island nation, thousands of miles from Moscow, and in Russia. 

"The Ministry of the Interior...is working on the neutralization and dismantling of a human trafficking network that operates from Russia to incorporate Cuban citizens living there, and even some from Cuba, into the military forces participating in war operations in Ukraine," the Cuban government statement said.

Russia last year announced a plan to boost the size of its armed forces by more than 30% to 1.5 million combat personnel, a lofty goal made harder by its heavy but of yet undisclosed casualties in the war.

In late May, a Russia newspaper in Ryazan city reported that several Cuban citizens had signed contracts with Russia's armed forces and had been shipped to Ukraine in return for Russian citizenship.

It was not immediately clear if the Cuban foreign ministry statement was associated with the Ryazan report.

But Cuba's government said it had already begun prosecuting cases in which its citizens had been coerced into fighting in Ukraine.

"Attempts of this nature have been neutralized and criminal proceedings have been initiated against people involved in these activities," the statement read.