China's foreign minister on Saturday said his country would vigorously defend its sovereignty, declaring there was "no room for compromise" with Japan over territory or history.

"We will never bully smaller countries yet we will never accept unreasonable demands from smaller countries," Wang Yi told reporters.

"On issues of territory and sovereignty, China's position is firm and clear: We will not take anything that isn't ours, but we will defend every inch of territory that belongs to us."

China is embroiled in disputes with several of its neighbours including the Philippines and Japan, with tensions centred on rival claims in the South China Sea and East China Sea.

Beijing asserts that almost all the South China Sea is its territory but the Philippines, Vietnam, Malaysia, Brunei and Taiwan have overlapping claims.

The dispute with Tokyo is particularly tense given historical animosities between the two countries over Japan's invasion of China in the 1930s and 40s.

Beijing and Tokyo both claim a small uninhabited archipelago in the East China Sea, administered by Japan as the Senkaku Islands, but which China calls the Diaoyu Islands.

Chinese officials and state media have this year demanded that Japan reflect on its historical aggression and atrocities, in much the same manner as postwar Germany has with its Nazi past.

"On the two issues of principle, history and territory, there is no room for compromise," Wang told reporters on the sidelines of the National People's Congress, China's communist-controlled legislature.

"If some people in Japan insist on overturning the verdict on its past aggression I don't believe the international community and all peace loving people in the world will ever tolerate or condone that."

Tensions between the two have risen markedly since 2012 when Tokyo purchased islands in the chain it did not already own from their private Japanese owners. Beijing has taken an increasingly hard line on the issue ever since.

Ships and aircraft from both countries regularly patrol waters around the contested territory and have on occasion come perilously close to armed clashes.

Some, including Japanese Prime Minister Shinzo Abe, have mentioned the dispute within the context of World War I, when European powers Germany and Britain went to war.

Wang, a career diplomat who has served at China's embassy in Tokyo and speaks Japanese, discounted such a comparison at the press conference.

"I wish to emphasise that 2014 is not 1914, still less 1894," he said. The latter year marks the start of the First Sino-Japanese War, which ended in victory by Japan in 1895, marking that country's rise as a regional power after more than two centuries of isolation.

"Instead of using Germany before the First World War as an object lesson, why not use Germany after the Second World War as a role model?" Wang added.

The United States, China and Japan are the world's three biggest economies, while Tokyo has a security pact with Washington, which is treaty-bound to come to its defence if it is attacked.

Wang became foreign minister in March last year as China completed a once-a-decade leadership transition that saw Communist Party General Secretary Xi Jinping become state president.

He reiterated Beijing's calls for dialogue to resolve the issue of the nuclear programme of North Korea, which receives most of its trade and aid from China.

"All along, we have a red line, that is we will never allow war or instability on the Korean peninsula," he said, adding that "mutual mistrust", particularly between Pyongyang and Washington, was preventing a resolution.

Wang also stressed the need for discussions in Ukraine, where forces of China's ally Russia are in effective control of Crimea.

"The priority now is to exercise calm and restraint and to prevent further escalation of the situation," he said. "The parties should carry out dialogue and consultation to put the issue on the track of a political settlement."

Despite tensions with the US over issues including mutual suspicions related to defence and cyber security, Wang gave an overall upbeat assessment of ties.

"The Asia-Pacific should be the testing ground of our commitment to build a new model of relations rather than a competitive arena," he said.