The prime ministers of Japan and Australia have signed a security pact designed to enhance military co-operation between the two nations.
Japan and Australia say the treaty benefits the region as a whole
Japan's PM Shinzo Abe said the pact would help to stabilise the region.
The defence deal - Japan's first with a country other than the US - includes co-operation on border security, counter-terrorism and disaster relief.
It is the result of closer co-operation on security matters in Asia that Japan and Australia have been pursuing.
The four part agreement Mr Abe signed with Australian PM John Howard in Tokyo sets out priorities for co-operation on counter-terrorism activities, maritime security, border protection and disaster relief.
Australia says the pact may lead to intelligence sharing and to Japanese troops taking part in military exercises on Australian soil.
Both countries are stressing though that this is not a mutual defence treaty like Tokyo has with Washington.
"The purpose of this is to express a common desire of Japan and Australia to work ever closer together to contribute to security in the region," Mr Howard said after meeting Defence Minister Fumio Kyuma.
"You never forget the past. You move on from the past, and you don't allow the past to contaminate what you do in the present or in the future," he said.
Japan's other defence treaty was signed in 1960, when the US guaranteed to defend Japan if it were attacked.
The US regards both as important strategic partners in this part of the world, and the three countries have held annual talks on security for the last five years, says the BBC's Chris Hogg in Tokyo.
Now Japan and Australia are pledging to hold additional meetings and to work more closely together.
Australia and Japan were described recently by the US as important strategic allies in the Asia-Pacific region, and both backed the US-led war in Iraq.
When Japanese troops were in Iraq last year, Australian soldiers were deployed to provide security for them.
The joint declaration comes amid regional concern over North Korea's nuclear and missile tests last year and wariness over China's growing military power.
But fears that Japan is moving away from its pacifist stance have been dismissed by Mr Abe.
He denies that the declaration is aimed at China, and Mr Howard says he is not worried it will harm Canberra's ties with Beijing.
Both Tokyo and Canberra point to the important trade ties and improving relationships both have with Beijing.
The talks between the two men are also expected to include contentious issues such as the row over Japan's wartime use of women as sex slaves.
Mr Howard says he will raise the issue after Mr Abe last month said there was no evidence that Japan's military or government had been involved in coercion.
He also wants to discuss Japan's insistence that it has a right to continue whaling.