I've translated a post from Google+ (tweeted by @knownowo in which someone explains what Chinese diplomatic language really means. It's more humorous than anything but I found it very interesting. For the actual diplomatic language I've left the Chinese above the English translations. Here it is:
China’s diplomatic condemnations. Japan’s already reached the second-to-last level --- dangerous!
我国是谴责大国经常被人调侃，但很少有人注意中国谴责时所用的的词汇，今日人民日报对日本关于钓鱼岛出现了悬崖勒马这个词，这已经是中国特色外交黑话属于倒数第二等级了
China is often mocked for denouncing great nations, but very few people notice the language China uses in these condemnations. Today’s People’s Daily used the phrase ‘stopping a horse just before a cliff” to refer to Japans’ purchase of the Diaoyu Islands. This is the second-to-last level of diplomatic phrases with Chinese characteristics.
亲切友好的交谈——字面意思；
Close, friendly talks – literal meaning
坦率交谈——分歧很大，无法沟通；
Frank talks – too many disagreements; can’t communicate
交换了意见——会谈各说各的，没有达成协议；
Exchanged opinions – in talks, people just spoke their own piece and didn’t reach any agreement
充分交换了意见——双方无法达成协议，吵得厉害；
Thoroughly exchanged opinions – neither party could reach an agreement after arguing fiercely
增进了双方的了解——双方分歧很大；
Improved both parties’ understanding – both parties have greatly divergent viewpoints
会谈是有益的——双方目标暂时相距甚远，能坐下来谈就很好；
The talks are beneficial – both parties’ goals are still greatly divergent, if they can sit down and talk it’ll be fine
我们持保留态度——我们拒绝同意；
We maintain our position – we refuse to agree
尊重——不完全同意；
Respect – don’t agree completely
赞赏——不尽同意；
Admire – don’t agree completely
遗憾——不满；
Regret – dissatisfied
不愉快——激烈的冲突；
Unhappy – conflict extremely
表示极大的愤慨——现在我拿你没办法；
Express great regret – there’s no way we can get at you now
严重关切——可能要干预；
Seriously pay attention to – we may intervene
不能置之不理——即将干涉；
Cannot ignore – about to intervene
保留做出进一步反应的权利——我们将报复；
Reserve the right to react further – we’re gonna get you back
我们将重新考虑这一问题的立场——我们已经改变了原来的（友好）政策；
We will take a new look at our stance on this matter – we have already changed our previous (friendly) policy
拭目以待——最后警告；
Wait and see – last warning
请于*月*日前予以答复——*月*日后我们两国可能处于非和平状态；
Please reply by XX/XX – After XX/XX our two countries may be in a state of non-peace
由此引起的后果将由*负责——可能的话我国将诉诸武力（这也可能是虚张声势的俗语）；
The consequences of this will be dealt with by * -- China may resort to force (or this may be an empty threat)
这是我们万万不能容忍的——战争在即；
This is something we absolutely cannot accept – war is imminent
这是不友好的行动——这是敌视我们的行动；可能引起战争的行动；
This is an unfriendly action – This is an action that sees us as an enemy, and may inspire acts of war
是可忍孰不可忍——不打算忍了，要动手了。
This is unendurable – We don’t plan to endure it, we’re going to strike
悬崖勒马——想被XX么？
Stopping the horse at the edge of the cliff – do you want to be XX’ed?
勿谓言之不预也——准备棺材吧。
Do not say that we didn’t warn you --- Prepare your coffins.
PS;最后一句中国只说过2次，印度和越南后面的事大家都知道了，不知道什么时候还能听到外交部说这句话
PS: The last sentence has been spoken by China only twice. We all know wat happened to India and Vietnam after that. No one knows the next time we’re going to hear that from the Ministry of Foreign Affairs.