INTERNATIONAL NEWS - But he also urged Mr Xi to "work very hard" on persuading North Korea to denuclearise.
On China's trade surplus, Mr Trump surprised many when he said he did "not blame China" for "taking advantage".
The US president was speaking in Beijing while on a state visit.
He is in the Chinese capital as part of his five-nation tour of Asia. The two leaders held talks earlier on Thursday after a grand welcome for Mr Trump.
They also announced the signing of $250bn (£190bn) worth of business deals during Mr Trump's visit, although it is unclear how much of that figure is past deals being re-announced or simply the potential for future deals.
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China 'can fix this problem'
Discussion on how to deal with North Korea's threats to the region has dominated Mr Trump's agenda and China is Pyongyang's main economic ally. Prior to his arrival in Beijing he urged China to sever ties with the North.
In speeches on Thursday Mr Trump said: China "can fix this problem easily and quickly".
Beijing has consistently said it is doing all it can, but Mr Trump added: "I am calling on (Mr Xi) to work very hard. I know one thing about your president. If he works on it hard, it'll get done".
He then thanked Mr Xi several times for efforts such as restricting trade with Pyongyang.
Mr Xi, for his part, said both sides would "continue to work towards" fully implementing UN sanctions and "enduring peace" on the Korean peninsula.
