South Korean actress Yoona attends the Busan International Film Festival on October 3, 2019. Photo: IC

The Busan International Film Festival, Asia's biggest gathering of its kind, will be reduced to a fraction of its usual scale with several sections moved online because of the coronavirus pandemic, organizers said Monday.

The event normally sees a host of industry figures from across Asia and further afield, including some from Hollywood, descend on the South Korean port city for 10 days of critical consideration and financial deal-making.

But South Korea - which largely overcame an early coronavirus surge with extensive tracing and testing - has seen several clusters in recent weeks, raising concerns of a second wave and prompting authorities to tighten social distancing measures in August.

Those curbs are being temporarily eased in the greater Seoul area, officials announced over the weekend, but Busan organizers said they had no choice but to cut back on the festival - which will also be delayed by two weeks.

"We agonized over whether we should go ahead with hosting the event," festival chairman Lee Yong-kwan told reporters.

And he hinted that it could still be canceled altogether if South Korea's traditional Chuseok harvest festival triggers a new surge in infections.

"There could be a situation in which we won't be able to host the event," he said.

Originally set for early October, organizers said it will be pushed back to October 21-30.

"All outdoor events are canceled, including the opening and closing ceremonies," organizers said, "in order to prevent crowds from gathering." 

"There will be no international invitations, nor will there be any receptions or parties hosted to provide networking opportunities for film industry professionals."

A total of 192 films from 68 countries will still be shown, but each movie will only be screened once, compared with two or three times in 2019.