Tehran on Saturday blasted U.S. President Donald Trump's travel ban on countries including Iran, saying it showed "deep hostility" toward Iranians and Muslims. "The decision to ban the entry of Iranian nationals - merely due to their religion and nationality - not only indicates the deep hostility of American decision-makers towards the Iranian people and Muslims but also

Iranians again face a U.S. travel ban imposed by President Donald Trump, with the decision drawing anger, frustration and some shrugs given the decades of tensions between the countries.

Here is a closer look at why the administration says it is instituting full bans on foreign nationals traveling to the U.S. from 12 nations.