US Secretary of State Rex Tillerson reiterated the United States readiness to act "alone" against North Korea, shortly after the US air strike that targeted an airfield of the Syrian regime after being accused of launching a chemical attack on civilians in the town of Khan Sheikun in Idlib a few days ago. 
Tillerson affirmed that the United States is ready to act alone of China did not cooperate to contain North Korea's nuclear ambitions which violate the international law. 
He noted a commitment between Washington and Beijing to work together to solve the North Korean file in a peaceful way. However, he stressed that North Korea must change its position before establishing a basis for dialogue or talks. 
Tillerson underlined that President Donald Trump and Chinese President Xi Jinping arrived at new agreements on North Korea during their two-day summit, noting that President Xi agreed to increase China’s cooperation with the US to pressure North Korea to end their nuclear program. 

Source: QNA