Hungary's prime minister lambasted his Croatian counterpart Friday, accusing him of being the envoy of a global left-wing organization with the job of attacking Hungary — some the strongest statements yet in neighborhood disputes caused by the migrant crisis.

Viktor Orban said that the parties in the Socialist International, which includes Croatian Prime Minister Zoran Milanovic's Social Democratic Party, support migration, think the wave of migrants reaching Europe is a "good thing" and their leaders "are following the orders not so much of their people as of the Socialist International."

Orban said on state radio that "we don't consider what the Croatian prime minister says to be the opinion of the Croatian people."

"When they hear the Croatian prime minister, I ask Hungarians not to hear a Croatian man but an envoy of the Socialist International who is supposed to attack Hungary," Orban continued, adding that he had refrained from criticizing Milanovic until now in the interest of the long-term relationship between their countries.

Hungary's foreign minister, Peter Szijjarto, last month called Milanovic's handling of the migrant crisis "pathetic" while Milanovic said Hungary's border fences were a disgrace.

Politicians from the two countries have been trading barbs since Hungary's decision on Sept. 15 to close its border with Serbia with a high fence protected by razor wire, police and soldiers.

Now, thousands of migrants a day are streaming into Hungary from neighboring Croatia — taking a longer route from Serbia en route to Austria as they search for clear routes toward Germany and other destinations in the European Union.

Hungarian officials say they are close to completing a fence on the Croatian border as well.