Foreign Minister Julie Bishop has stepped up calls for China to rein in rogue state North Korea.
The North Korean nuclear threat has dominated Ms Bishop's and Defence Minister Marise Payne's talks with their Japanese counterparts.
"We believe that more should and could be done by China," Ms Bishop said in Tokyo, reflecting on the two countries' "unique" relationship.
China is the source of virtually all of North Korea foreign direct investment, trade and energy, she said.
Ms Bishop flagged North Korea will be the subject of further sanctions.
"The idea behind the sanctions is to send the clearest possible message to North Korea that its behaviour will not be tolerated, that a nuclear-armed North Korea is not acceptable to our region," she said.
Ms Bishop and Senator Payne also met with Japanese Prime Minister Shinzo Abe during their visit.
The trip comes amid signs North Korea is planning to carry out another nuclear test.
Pyongyang has enhanced its nuclear and missile programs under leader Kim Jong Un, conducting two nuclear tests and launching about 20 ballistic missiles last year alone.
US Vice President Mike Pence was in Japan on Wednesday and said North Korea poses the "most dangerous and urgent threat" to the Asia-Pacific region.
