Philippine President Rodrigo Duterte said Saturday he would not sever his nation's alliance with the United States, as he sought to clarify his announcement that he planned to "separate".

"It's not severance of ties. Severance is to cut diplomatic relations. I can not do that. Why? It's in the best interests of my country that I don't do that," Duterte told reporters in his hometown of Davao after returning from China.