NASA and Pentagon officials moved swiftly this past week to urge competitors to Elon Musk’s SpaceX to more quickly develop alternative rockets and spacecraft after President Donald Trump threatened to cancel Space X’s contracts and Musk’s defiant response.

Trump and Musk are engaging in public fights on social media. Here’s a timeline of the highs and lows of Musk and Trump’s bromance.

Trump added that he has "no intention of speaking" to Musk anytime soon, saying "I’m too busy doing other things.”