China has demarcated an "air-defence identification zone" over an area of the East China Sea, covering islands that are also claimed by Japan.

China's defence ministry said aircraft entering the zone must obey its rules or face "emergency defensive measures".

The islands, known as Senkaku in Japan and Diaoyu in China, are a source of rising tension between the countries.

Japan lodged a strong protest over what it said was an "escalation".

Since President Xi Jinping took power a year ago, he has overseen a more muscular effort to assert Chinese control over disputed territories in East and South China seas.

His nationalist approach, backed-up by large increases in spending on the armed forces, is welcomed by many in China. But it has led to increasing tension with almost all of China's neighbours. Many, like Japan, have defence agreements with the United States, which has long sought to preserve the balance of power in Asia.

The fear is that one small incident, for example between Chinese and Japanese vessels or aircraft, could escalate rapidly into a far wider and more serious crisis.

"Setting up such airspace unilaterally escalates the situations surrounding Senkaku islands and has danger of leading to an unexpected situation," Japan's foreign ministry said in a statement.

Taiwan, which also claims the Diaoyu/Senkaku islands, expressed regret at the move and promised that the military would take measure to protect national security.

In its statement, the Chinese defence ministry said aircraft must report a flight plan, "maintain two-way radio communications", and "respond in a timely and accurate manner" to identification inquiries.

"China's armed forces will adopt defensive emergency measures to respond to aircraft that do not co-operate in the identification or refuse to follow the instructions," said the statement.

It said the zone came into effect from 10:00 local time (02:00GMT) on Saturday.

State news agency Xinhua showed a map on its website covering a wide area of the East China Sea, including regions very close to South Korea and Japan.

Responding to questions about the zone on an official state website, a defence ministry spokesman, Yang Yujun, said China set up the area "with the aim of safeguarding state sovereignty, territorial land and air security, and maintaining flight order".

"It is not directed against any specific country or target," he said, adding that China "has always respected the freedom of over-flight in accordance with international law".

map of east china sea and declared air defence zone
"Normal flights by international airliners in the East China Sea air-defence identification zone will not be affected in any way."

The islands have been a source of tension between China and Japan for decades.

In 2012, the Japanese government bought three of the islands from their Japanese owner, sparking mass protests in Chinese cities.

Since then, Chinese ships have repeatedly sailed in and out of what Japan says are its territorial waters.

In September this year, Japan said it would shoot down unmanned aircraft in Japanese airspace after an unmanned Chinese drone flew close to the disputed islands.

China said that any attempt by Japan to shoot down Chinese aircraft would constitute "an act of war".

Last month Japan's defence minister, Itsunori Onodera, said China's behaviour over the disputed East China Sea islands was jeopardising peace.

BBC World Service East Asia editor Charles Scanlon says the confrontation over the small chain of uninhabited islands is made more intractable by conflicting claims for potentially rich energy resources on the sea bed.

But the issue has now become a nationalist touchstone in both countries, making it hard for either side to be seen to back down, he says.

 Dreadclaw69 wrote:
China has our purse strings so I don't see us doing a lot. Maybe this gets referred to the UN

 Dark Apostle 666 wrote:
Of course, invade China!
What could possibly go wrong?

 Dreadclaw69 wrote:
China has our purse strings so I don't see us doing a lot. Maybe this gets referred to the UN

 Kilkrazy wrote:
Au contraire. The USA owes China a colossal fortune of dollars, not to mention the trade imbalance and technology transfers.

Nothing could be better than a short war allowing all those debts to be annexed and repudiated.

 djones520 wrote:
I expect to see more hemming and hawwing. China gets an Aircraft carrier, so what. They upgrade bomber capabilities and can launch nuclear missiles to the US, oh well. Their drastically increasing military expenditures, nothing to worry about.?

 Ouze wrote:

 djones520 wrote:
I expect to see more hemming and hawwing. China gets an Aircraft carrier, so what. They upgrade bomber capabilities and can launch nuclear missiles to the US, oh well. Their drastically increasing military expenditures, nothing to worry about.?

I know that when your only perceived tool is a hammer; every problem looks like a nail - invading-country-wise - but have some perspective. Russia has had nuclear missiles pointed at this country for over 50 years, and they weren't economically dependant upon us.

 djones520 wrote:
They most likely aren't recreating the rise of the 3rd Reich, but they've increased their military spending by roughly 800% over the last 13 years..

 AlexHolker wrote:

 djones520 wrote:
They most likely aren't recreating the rise of the 3rd Reich, but they've increased their military spending by roughly 800% over the last 13 years..

And yet the United States still spends four times that amount.

 generalgrog wrote:
What the heck is so important about these islands anyway?

This sounds more like sabre rattling than anything else.

GG

 djones520 wrote:

 generalgrog wrote:
What the heck is so important about these islands anyway?

This sounds more like sabre rattling than anything else.

GG

Fishing and mineral rights mostly, plus territorial sovereignty. We wouldn't to happy if China just decided to start camping out on some of our uninhabited Pacific Islands, and claimed them as their own.

 djones520 wrote:

 AlexHolker wrote:

 djones520 wrote:
They most likely aren't recreating the rise of the 3rd Reich, but they've increased their military spending by roughly 800% over the last 13 years..

And yet the United States still spends four times that amount.

Your point?

 AlexHolker wrote:

 djones520 wrote:

 AlexHolker wrote:

 djones520 wrote:
They most likely aren't recreating the rise of the 3rd Reich, but they've increased their military spending by roughly 800% over the last 13 years..

And yet the United States still spends four times that amount.

Your point?

That the Sinophobia routine is a bit rich coming from the country that spends four times as much in pure monetary terms and twice as much as a percentage of GDP.

 Kilkrazy wrote:

 Dreadclaw69 wrote:
China has our purse strings so I don't see us doing a lot. Maybe this gets referred to the UN

Au contraire. The USA owes China a colossal fortune of dollars, not to mention the trade imbalance and technology transfers.

Nothing could be better than a short war allowing all those debts to be annexed and repudiated.

Not that a clever diplomat would say such a thing out loud.

 generalgrog wrote:
What the heck is so important about these islands anyway?

This sounds more like sabre rattling than anything else.

GG

 Kilkrazy wrote:
List of countries that would support Japan versus China:

USA
Canada
UK
Poland
France
Belgium
Holland
Italy
Germany
Sweden
Norway
Denmark
Thailand
Singapore
Taiwan
Australia
New Zealand
The Philippines
South Korea


List of countries that would support China versus Japan:

North Korea

 Kilkrazy wrote:
List of countries that would support Japan versus China:

USA
Canada
UK
Poland
France
Belgium
Holland
Italy
Germany
Sweden
Norway
Denmark
Thailand
Singapore
Taiwan
Australia
New Zealand
The Philippines
South Korea


List of countries that would support China versus Japan:

North Korea

 Jihadin wrote:
We had missiles in the 30's?