To Japan they're the Senkaku Islands. To China they're the Diaoyu Islands.

Key points: Both nations claim historical ties to the disputed islands

Both nations claim historical ties to the disputed islands China has stepped up military activity around the islands

China has stepped up military activity around the islands Tension a cause for concern among leaders at G20, ASEAN summits

They are a group of eight tiny uninhabited islets or rocks in the East China Sea, north-east of Taiwan and geographically closer to China than Japan.

Japan has claimed ownership of the islands since 1895, and says there was never any trace of them being under the control of China's Qing Dynasty.

The islands were not included in territory which Japan renounced under the 1951 peace treaty that legally defined the territory of Japan after World War II and Japan says China has only shown interest in the islands since surveys in the 1970s indicated possible oil resources in the area.

But China says there are no Japanese records of the Diaoyu Islands ever being part of Japan.

The Foreign Ministry in Beijing says a study of Chinese books and documents show the islands have always belonged to China.

Despite decades of relative calm, China has stepped up military activity around the Senkaku Islands, and in recent weeks hundreds of Chinese fishing boats and Government ships entered waters around the disputed islands, infuriating Tokyo.

The maritime spat mirrors the long-running dispute over China's territorial ambitions in the South China Sea, where several nations, including the Philippines, Vietnam and Malaysia, have challenged China's claim to a series of small islands, islets, cays and reefs.

Tensions in the East China Sea have escalated alarmingly in recent months and threaten to become a new flashpoint between two countries that are no strangers to war.

Leaders refuse to back down despite meeting

At the G20 summit on Monday, China's leader Xi Jinping and Japan's Prime Minister Shinzo Abe held their first meeting in more than a year and agreed to improve relations.

But neither side would back down on the maritime dispute.

Mr Abe labelled recent incursions by Chinese vessels near the islands "regrettable".

Mr Xi said the two countries should resolve the issue through dialogue and consultation, again mirroring its stance in the South China Sea, where Beijing refused to respect arbitration by the Permanent Court of Arbitration.

Mr Abe has criticised China for rejecting the court's ruling, which found China had no legal grounds to its territorial claims.

He says the dispute must be solved under international law, not through power or intimidation.

China and Japan have been at war several times in the past 150 years. A stalemate over the second Sino-Japanese war in 1940 ultimately led to World War II in the Pacific.

There is nothing to suggest the scrap over a few tiny, uninhabited islands is about to cause World War III.

But history shows just how important the China-Japan relationship is to peace and stability in the wider region.

Consider too Japan's recent abandonment of its pacifist constitution — meaning Japanese soldiers can engage in foreign combat for the first time in 70 years — and the rise in Chinese nationalist sentiment, and it's not hard to see what is at stake.

Understandably the Senkaku/Diaoyu dispute was cause for worry among leaders at both the G20 summit and the ASEAN summit in Vientiane this week — alongside concerns over developments in the South China Sea.

While little progress was made, the two leaders agreed to restart talks later this month on joint development in the region, which may help to defuse tensions over the disputed islands.