The summit in Washington will be part of a five-day state visit by the Philippine leader designed to clarify the implementation of the 1951 Mutual Defense Treaty.
While the U.S. frequently makes such voyages to challenge China's territorial claims in the strategic waterway, the latest one took place as Beijing staged war games around Taiwan.
Xi told Putin in their meetings in Moscow that China "does not take either side" regarding the territorial row, a source said, ditching a long-held stance of recognizing them as Tokyo's.