In a press briefing at the White House, Bolton, when asked to confirm whether Trump will meet with the Saudi leader, said that Trump's "bilateral schedule is full to overflowing at this point."
However, he did not exclude the possibility of the two leaders' informal meeting.
Bolton also said that Trump, during his stay in the South American nation, is expected to meet with the presidents of Argentina, South Korea, Turkey, Russia as well as Japanese Prime Minister Shinzo Abe.
Trump's meeting with Abe "will transform at some point during that meeting into a trilateral meeting" with Indian Prime Minister Narendra Modi, Bolton added.
Also at the press briefing, White House spokesperson Sarah Sanders said that Trump's "participation in the G20 summit is a key opportunity to reiterate his commitment to domestic and global economic growth and prosperity, cement relations with other world leaders and advance a global economic system that is based on fair economic competition and free, fair and reciprocal trade."
Speaking of the prospect of U.S.-Saudi leaders' meeting, Sanders said she would not rule out any interaction, adding that Trump will also meet with German Chancellor Angela Merkel.
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