WASHINGTON, July 1 (Reuters) - US President Donald Trump

on Tuesday said billionaire Elon Musk is upset because he lost

the mandate for electric vehicles in the recent tax and spending

bill, and warned that the Tesla CEO "could lose a lot

more than that."

Earlier in the day, Trump suggested the government

efficiency department should review the subsidies Musk's

companies have received in order to save money, reigniting a war

of words between the world's most powerful man and its richest.