The meeting Friday in the casual setting of the Sunnyland estate outside Los Angeles was to be the first for the two men since Xi became the communist country's leader, CNN reported.
It will be "an attempt to set out the ground rules for how our two countries will work together in the 21st century," said Kurt Campbell, who until recently was U.S. assistant secretary of state for East Asian and Pacific Affairs.
The meeting is of "profound historic and strategic significance," said Chinese Foreign Ministry spokesman Hong Lei.
Cybersecurity and North Korea are expected to top the agenda.
Washington has repeatedly accused Beijing of cyberattacks on American businesses and government agencies. China has denied the charges, saying that hacking is a global problem.
Some progress is possible on North Korea, Campbell said.
China has "just about had it" with North Korea, he said.
North Korea's intransigence on Western concerns about its nuclear weapons program has created a context for heightened military actions by the United States "that ultimately are not in China's best strategic interests," Campbell said.
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