Japan and France have publicly expressed their disagreement over EU plans to lift an arms embargo on China.
Japan says lifting the China arms ban is dangerous for the region
Prime Minister Junichiro Koizumi said Japan was opposed to the move, which it fears could upset the military balance in East Asia.
But President Jacques Chirac said there would be safeguards on "sensitive" arms and technology exports to Beijing.
He said conditions had changed since the ban imposed after the repression of the Tiananmen Square protests in 1989.
"I indicated to him that the decision of the European Union does not imply a change in exports of sensitive arms or technology to China, as they are subject to rules which cannot be broken," Mr Chirac said.
The ban was political and no longer appropriate, he insisted.
"The conditions are not the same as when it was put in place. It is no longer valid," he added.
Mr Chirac also restated France's support for Japan's bid to secure a permanent seat on the United Nations Security Council.
The two leaders spoke after holding talks in Tokyo as part of Mr Chirac's three-day visit to Japan, which began on Saturday.
On Monday, Mr Chirac is due to speak at a seminar and have lunch with Emperor Akihito and Empress Michiko before returning to France on Tuesday.
Mr Koizumi also said Japan had no intention of giving up its bid to develop a $13bn (£7bn) experimental nuclear fusion reactor, which France also wants to host.
France and Japan have been at loggerheads over the International Thermonuclear Experimental Reactor (Iter) for some time.
Chirac visited the World Expo
The reactor will produce energy from nuclear reactions like the ones that power the Sun, and is seen as a test bed to create clean, inexhaustible energy before 2050.
Tokyo wants the reactor to be built at Rokkasho in northern Japan. But Paris has been lobbying for Cadarache in France.
The six international partners in the Iter project - the EU, Russia, China, the US, Japan and South Korea - are deadlocked on where to locate the reactor.
The EU made it clear earlier this month that it would not wait beyond June to reach international agreement for such a decision.
On Saturday, the French president praised what he described as the dynamism of economic relations between the two countries.
Addressing a group of businessmen in Osaka, southern Japan, Mr Chirac said about 500 French companies were operating in Japan, while some 400 Japanese organisations had been established in France.
The French president said this economic co-operation should be encouraged, particularly in the energy and transport sectors.
France is the largest foreign investor in Japan, according to French government statistics.
During the first day of his visit, Mr Chirac attended the World Expo - dedicated to sustainable development - in Aichi province, central Japan.
An avid sumo wrestling fan, the French president was seen later on Saturday at a tournament in Osaka.