South Korean President Moon Jae-in remains silent during a funeral mass at Namchun Catholic Church in Busan, Thursday, held for his mother, Kang Han-ok. Yonhap

South Korean President Moon Jae-in was gearing up for a round of hectic summit diplomacy in November, but it faces some uncertainty from Chile's abrupt announcement to call off an Asia-Pacific Economic Cooperation (APEC) meeting.

Moon planned to attend the two-day session, supposed to open in Santiago on Nov. 16, following a one-night stopover in Mexico for bilateral summit talks with President Andres Manuel Lopez Obrador.

In the Chilean capital, Moon was seeking to hold one-on-one summits with some of the 19 other participants in APEC, including U.S. President Donald Trump, Chinese President Xi Jinping and Russian President Vladimir Putin, on the sidelines of the annual gathering.

Cheong Wa Dae initially responded cautiously to Chile's decision.

"We are aware of the news. We will have to keep an eye on (related) situations, going forward," Cheong Wa Dae spokesperson Ko Min-jung said in a brief text message sent to reporters Wednesday night.

The next morning, a Cheong Wa Dae official said Chile's announcement has caught those who have prepared for Moon's APEC attendance off guard. The president is on special leave due to the loss of his mother earlier this week.

"I think we are going to have to reschedule the November schedule," he said.

In this photo released by Chile's presidential office, President Sebastian Pinera, center, accompanied by Chile's Foreign Minister Teodoro Ribera, left, and Environment Minister Carolina Schmidt, announces that he is calling off the Asia-Pacific Economic Cooperation Economic Forum, APEC, and Climate Change COP25 Conference, at La Moneda presidential palace in Santiago, Chile, Wednesday, Oct. 30, 2019. AP-Yonhap

He did not rule out the possibility that APEC members will seek an alternative venue. He pointed out media reports that Trump, in particular, has been looking forward to joining this year's APEC summit in search of a breakthrough trade deal with Xi.

The White House said it still hopes for Trump-Xi talks in November despite Chile's move. Technically, Chile has withdrawn as host of this year's APEC, and it can take place at another location.