美国有线新闻 CNN 伊朗试射导弹引发美新制裁 美伊关系再度紧张（在线收听）

First, though, tensions between the U.S. and the Middle Eastern nation of Iran. Earlier this week, Iran tested out a medium range missile, a U.S. defense official said the test failed and that there was no threat to America or its allies in the Middle East.

But do Iran's missile tests break international law? A U.N. Security Council resolution passed in 2015 tells Iran not to have anything to do with missiles that can carry nuclear weapons. Iran has tested several missiles since then, but it says the resolution does not apply because its missile program is only for defensive purposes.

The U.S. doesn't agree. On Wednesday, America's national security adviser called Iran's recent tests a provocative breach of the resolution and said the U.S. was putting Iran on notice. Iran responded that it would vigorously continue its missile activity and that it didn't need permission to do it.

Trump administration officials say they're planning to impose additional sanctions, penalties on certain people or businesses affiliated with Iran.