President Donald Trump on Thursday predicted that an upcoming meeting with Chinese leader Xi Jinping would be "very difficult," as he set an adversarial tone ahead of a high-profile summit. 

"The meeting next week with China will be a very difficult one," Trump tweeted, in apparent reference to the Mar-a-Lago meeting beginning next Thursday. 

"We can no longer have massive trade deficits... and job losses. American companies must be prepared to look at other alternatives."