Czech President Milos Zeman speaks during the 70th session of the United Nations General Assembly at the U.N. Headquarters in New York, Sept. 29, 2015. He has denounced Middle Eastern refugees as invaders. Reuters / Eduardo Munoz

Czech President Milos Zeman denounced refugees entering Europe as "an organized invasion," Agence France-Presse reported Saturday. Zeman, who was elected in 2013, has previously made comments hostile to refugees, many of whom are fleeing conflict-torn homelands like Syria and Iraq.

In his Christmas address to the country, Zeman said the young men coming to the Czech Republic from the Middle East should instead "take up arms" against the Islamic State group at home. The extremist group, also known as ISIS or ISIL, controls swaths of territory across Syria and Iraq. Some 1 million refugees have arrived in Europe this year, half of whom were Syrians.

"A large majority of the illegal migrants are young men in good health, and single. I wonder why these men are not taking up arms to go fight for the freedom of their countries against the Islamic State," said Zeman, 71, according to AFP.

Zeman has become known for expressing anti-immigrant sentiments and in November attended an anti-Islam rally in Prague, according to German state broadcaster Deutsche Welle‎. Zeman said it was possible to have compassion for refugees that are sick, elderly or are children, but said young male refugees are only strengthening ISIS by leaving their home countries. He further compared their journey unfavorably to Czechs leaving when the country was under occupation by Nazi Germany from 1939 to 1945, saying the Czechs intended to "fight to liberate the country and not to receive social benefits in Great Britain," according to Agence France-Presse.

Zeman also said he felt like the only voice warning against the threat and made a reference to the Trojan War. "Sometimes I feel like Cassandra, warning the Trojans not to bring the horse into the city," he said, according to Deutsche Welle.

Czech Prime Minister Bohuslav Sobotka has spoken out against the head of state before and said the Christmas message was based "on prejudices and his habitual simplification of things," according to Agence France-Presse. Deutsche Welle reported few refugees who pass through the Czech Republic have chosen to stay.