President Donald Trump's policy on Iran has been straightforward all along, Secretary of State Mike Pompeo said Friday: Stop being a world sponsor of terror.

"We have made it clear that regime change is not President Trump's policy," Pompeo told MSNBC's Andrea Mitchell.  "We have laid it out what we want from the Islamic Republic of Iran...stop launching missiles into Riyadh, and threatening Hezbollah, and ceasing to be the world's state sponsor of terror."

When Iran's governing regime makes those changes, the Trump administration will be "happy" to have a conversation with its leaders, Pompeo said. "President Trump has made it clear, but there are no signs that they are backing off and continuing the terror threats around the world."

Meanwhile, Pompeo told Mitchell that he finds it offensive that people are suggesting the administration is continuing to work in Yemen to avoid jeopardizing arms sales to Saudi Arabia and others.

"The reason that we are continuing to work in Yemen is to support the peace resolution, and we support that effort," said Pompeo. "The killing of the children is tragic, and the Saudis have taken responsibility for that and the secretary and myself have worked closely with the Saudi-led coalition to reduce the risk of casualties and civilian collateral damage. They are imperfect, but we are working toward that end."

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