The very public budget fight between the defense secretary and the Navy could serve as an alarm to President-elect Trump that he needs to pay attention to the shipbuilding portion of the fiscal year 2018 budget, according to one expert.

Navy Secretary Ray Mabus sent a memo to Defense Secretary Ash Carter this week informing him that he would be ignoring the top line provided by the Pentagon in his budget submission for fiscal year 2018, because adhering to it would impede the Navy from performing its mission. The Pentagon reportedly asked him to cut about $17 billion over the next five years from the sea service’s budget.