Leaders of the Group of Seven (G7) industrialized nations fell short of endorsing Japan's anti-China rhetoric at a meeting in Brussels on Wednesday.

"We are deeply concerned by tensions in the East and South China Sea," the leaders from Britain, Canada, France, Germany, Italy, Japan and the United States said in a communique issued at the end of the first day of their talks in Brussels.

"We oppose any unilateral attempt by any party to assert its territorial or maritime claims through the use of intimidation, coercion or force," the G7 leaders said, without specifying any country.

Japan had reportedly pushed the G7 to single out China for the rising tensions in the East and South China Sea, hoping to apply international pressure on China in its territorial disputes with Beijing over the Diaoyu Islands.

In an earlier response to Tokyo's futile attempt, the Chinese foreign ministry reaffirmed the country's determination to protect its sovereignty and legitimate rights.

"China is firm and resolute in safeguarding the sovereignty and maritime rights and interests in the East China Sea and the South China Sea as well as national security," Foreign Ministry spokesman Hong Lei told reporters on Tuesday.

"I want to point out that on the East China Sea issue, it is not China but Japan who changes the status quo. It is Japan who snatched the Diaoyu Islands away from China by force over 100 years ago. It is also Japan who attempted to unilaterally 'nationalize' the Diaoyu Islands by violating the UN Charter, the Cairo Declaration, the Potsdam Declaration and other international laws," he said.

"Therefore it is Japan who should clean up its acts and correct its mistakes," the spokesman said.

"Meanwhile, we always hold the point that disputes should be managed and settled through dialogue and negotiation. We advise the Japanese side not to stir up troubles nor mislead the public opinion on international occasions."

The two-day summit hosted by the European Union (EU) focuses on Ukraine situation, ties with Russia, global economy and energy security, according to preliminary agenda unveiled by the EU.

Originally, a G8 summit was scheduled to take place in Sochi, Russia in early June under Russian presidency. At their meeting in The Hague, the Netherlands on March 24, the G7 leaders decided to meet in Brussels in June in the G7 format instead to protest the accession of Ukraine's Crimea region into Russia.