U.S. President Donald Trump's travel ban has been applied Sunday in Istanbul's Atatürk Airport, with airport staff preventing passengers who did not meet required conditions from boarding U.S.-bound flights.

Last week, President Trump ratified an executive action which brought into force a travel ban to the U.S. for the nationals of countries deemed to be supportive of terror, namely Iran, Iraq, Syria, Libya, Somalia, Sudan, and Yemen.

Trump's decision created outrage across the world, but nonetheless had to be applied by several international airline companies, including Turkish Airlines, Turkey's national flag carrier airline company.

The U.S. president's decision created controversy in Istanbul' Atatürk Airport on Sunday as several passengers, who were nationals of the countries affected by the travel ban, were prevented from boarding flights for the U.S.

Some passengers were seen crying after learning that their visa for the U.S. had been cancelled at the last minute.

The Turkish Airlines' staff applied the decree, issued following Trump's ban.

''I have a Syrian passport. I came here in order to take the flight, after fulfilling all necessary conditions and requirements, but I now learn that my visa had been cancelled. My wife and my child have been in the U.S. for two year,'' said 32-year-old Nail Zaion who was denied access to the Turkish Airlines's Los Angeles-bound flight.

Zaion was forced to cancel his ticket.