Hungary’s anti-immigration prime minister has described stopping a massive influx of migrants through the Balkans as Europe’s only success in dealing with the problem.

Viktor Orban on Tuesday offered to help small Montenegro guard its borders against migrants, insisting that the Balkans should remain closed for people trying to reach Western Europe.

Orban says after talks with Montenegrin PM Dusko Markovic that “Europe is still making serious mistakes.” He adds that “the only success has been the closure of the Balkan route, which was thanks to Hungary.”

Orban’s government has built two rows of razor-wire fence on its southern border with Serbia after hundreds of thousands of migrants passed through in 2015.

Some migrants recently have turned also to Montenegro and Bosnia for a passage to the West.