President Donald Trump’s phone calls with international leaders caused at least two diplomatic incidents before he picked a Twitter fight with Iran on Thursday ― bringing the U.S. into spats with three nations key to American interests in less than a week.

Trump’s actions have not only caused rifts with countries that are often hostile to the U.S., like Iran, but also with reliable allies like Australia. They suggest that U.S. foreign policy under Trump will be unpredictable, and that when the president feels challenged, there are international repercussions.

Trump’s most unexpected fight so far came during his call with Australian Prime Minister Malcolm Turnbull on Saturday. Trump apparently became irate when Turnbull attempted to confirm that the U.S. would uphold an Obama-era agreement for the U.S. to take in up to 1,250 refugees from an Australian detention center, according to a report by The Washington Post.

Turnbull allegedly hit a nerve and Trump reportedly flew off the handle, accusing Australia of trying to export the “next Boston bombers.” Trump and Turnbull then entered into a heated exchange that Trump told the Australian prime minister was the “worst call by far” he’d had with world leaders.

According to the Post, Trump hung up 20 minutes into what should have been an hour-long chat. He tweeted out a statement on Wednesday referring to the refugees as “illegal immigrants,” and calling the agreement a “dumb deal.”

Jonathan Ernst/Reuters This phone call doesn't even appear to be going well. Donald Trump, Michael Flynn and Steve Bannon on the line with Australian Prime Minister Malcolm Turnbull on Jan. 28, 2017

Australia and the U.S., close and longtime allies, now face a diplomatic dispute over the refugee agreement. On Thursday, Sen. John McCain (R-Ariz.) tried to mend some of the damage by calling Australia’s ambassador to the U.S., Joe Hockey, to reaffirm the two countries’ alliance. The fate of the refugees, who are living in harsh conditions in island detention camps, is unclear.

Trump also had a testy diplomatic call with Mexican President Enrique Peña Nieto last Friday, according to an explosive Associated Press report published on Wednesday. During an hour-long phone conversation with the Mexican leader, Trump reportedly said he was ready to send U.S. troops to stop “bad hombres down there” if the Mexican military didn’t step up. The AP said it had based its report on an excerpt of a transcript of the call that didn’t include information about Trump’s tone or Peña Nieto’s response.

According to an excerpt of the transcript of the call provided to CNN, Trump said, “You have some pretty tough hombres in Mexico that you may need help with. We are willing to help with that big-league, but they have [to] be knocked out and you have not done a good job knocking them out.”

Mexico denied the report, insisting that the conversation between both leaders was respectful and constructive.

Relations between the U.S. and Mexico have been particularly rocky in the past week. Last Wednesday, Trump ordered the construction of a wall on the U.S.’ southwest border and tweeted that Mexico would foot the bill, a promise he made throughout his presidential campaign (and one that Mexican leaders have repeatedly derided). Peña Nieto canceled a planned visit to Washington D.C. over Trump’s remarks, while Trump insisted on Twitter that both leaders had mutually agreed on the cancellation.

Miguel Tovar/STF via Getty Images Wax replicas of U.S. President Donald Trump and Mexican President Enrique Peña Nieto on display in Mexico City on Feb. 2, 2017. The two leaders were supposed to meet in Washington D.C. on Jan. 31, but the visit was cancelled.

Finally, Trump’s national security adviser, Michael Flynn, took aim at Iran on Wednesday, putting Tehran “on notice” over a ballistic missile test it conducted over the weekend.

The president echoed the threat on his Twitter account on Thursday. “Iran has been formally PUT ON NOTICE for firing a ballistic missile. Should have been thankful for the terrible deal the U.S. made with them!” Trump tweeted.

Flynn’s statement did not include details about any steps the administration is considering. A Pentagon spokesperson said on Wednesday that the U.S. military did not change its posture toward Iran.

Iran did not waste time in hitting back. It wasn’t the first time “an inexperienced person” has threatened Iran, Ali Akbar Velayati, an adviser to Iran’s supreme leader, Ayatollah Khamenei, said on Thursday. “The American government will understand that threatening Iran is useless,” Velayati added, according to Fars News.

Trump has routinely vowed to take a hard line on Iran and described the multilateral agreement to limit the country’s nuclear abilities as “the worst deal ever.”

Despite the fiery statements and revelations, Trump’s White House team has reported on numerous “constructive” communications with foreign leaders ― and Trump himself has tried to downplay the reports of his more negative interactions with foreign governments.

“When you hear about the tough phone calls I’m having, don’t worry about it. Just don’t worry about it. They’re tough,” Trump said during the National Prayer Breakfast on Thursday morning.

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