Japan and Australia expressed "grave concern" Thursday about China's imposition of a national security law on Hong Kong, saying the region's autonomy has been eroded.

During their first virtual summit, Prime Minister Shinzo Abe and Australian Prime Minister Scott Morrison agreed that the two nations will step up preparations to resume limited travel among businesspeople, with Tokyo enforcing an entry ban on 129 countries and regions amid the global coronavirus pandemic.

"The leaders shared grave concern about the imposition of a national security law in Hong Kong, as it eroded Hong Kong's autonomy under the 'One Country Two Systems' framework," a statement issued after the talks said.