US President Donald Trump has begun talks with Chinese leader Xi Jinping in Beijing, following his lavish welcome to the Chinese capital.
Mr Trump is expected to raise how China can rein in North Korea's nuclear aims, an issue dominating his Asia tour.
The US wants China, Pyongyang's main ally, to apply further pressure, but Beijing says it is doing enough.
The leaders of the world's two largest economies are also expected to discuss their trade deficit.
Earlier in the five-nation trip, Mr Trump urged North Korea to make a deal to end its nuclear weapons programme, while also warning it against further provocation against the US and the world, saying: "Do not try us."
Mr Trump has tweeted at least four times since arriving in China - where Twitter is banned. But a White House official told reporters that he would "tweet whatever he wants".
Mr Trump is in China as part of a five-nation tour of Asia. He has already visited South Korea and Japan, and will go on to Vietnam and the Philippines later in the week.