President Trump said that the U.S. military is considering "strong options" on Iran ahead of meeting the country's leaders.

On Sunday, when asked on Air Force One whether Iran is crossing a red line, Trump told reporters, “they’re starting to, it looks like,” The Hill news outlet reported.

“There seemed to be some people killed that aren’t supposed to be killed,” he said. “But we’re looking at it very seriously. The military is looking at it and we’re looking at some strong options and we’re going to making a determination.”

Trump added that he is receiving “an hourly briefing” on the situation regarding Iranian protesters. 

He also said that Iranian leaders called him on Saturday, wanting to negotiate. 

“I think they’re tired of being beat up by the United States,” Trump said. 

“Iran wants to negotiate, yes. We may meet with them, I mean a meeting is being set up,” he continued. “But we may have to act, because of what’s happening, before the meeting. But a meeting is being set up, Iran called, they want to negotiate.”

Protests against Iran's leadership have continued for weeks, resulting in 538 people dying and 10,600 others being detained, according to the U.S.-based Human Right Activists News Agency. The exact numbers are difficult to determine because the internet and phone lines in Iran are cut off.

Trump said that he was going to speak with Elon Musk about potentially using the SpaceX-operated satellite constellation to help Iranians amid the internet blackout.