By Daniel Griffiths
BBC News, Beijing
Wen Jiabao called on North Korea to refrain from launching missiles
China is one of North Korea's few remaining allies - Beijing supplies the impoverished regime in Pyongyang with much needed fuel, food and energy.
In the past few weeks several senior Chinese officials including Prime Minister Wen Jiabao, had repeatedly called on North Korea to abandon its plans for missile tests, saying they would increase regional tensions.
So these tests are a real slap in the face for China, and a sign for some that it might have less influence in North Korea than has often been suggested.
But the US says it still believes China holds the key to a solution on the Korean peninsula. Washington's representative, Christopher Hill, is due in Beijing at the end of the week.
Mr Hill has already made his position clear: "We need China to be very, very firm with their neighbours and frankly with their long-term allies the North Koreans, on what is acceptable behaviour and what is not acceptable behaviour."
There is anger in Beijing about the missile tests, especially as Chinese leaders lobbied hard for North Korea to refrain from the launches.
But for China the situation is extremely complex. There is no doubt that as such a major supplier of aid to North Korea it does have some leverage.
And it is concerned about North Korea's military and nuclear ambitions - worrying that they might start an arms race in northeast Asia.
But at the same time Beijing does not want to cut off aid to North Korea because it fears the regime in Pyongyang might collapse and create a flood of migrants, destabilising neighbouring countries including China.
That means Beijing is opposed to any international sanctions and has already made that position clear.
Christopher Hill is due to visit Beijing this week
It still says diplomacy is the best way to deal with North Korea as the best way to find a solution to the impasse on the Korean peninsula. It will urge all countries to resume the stalled six-nation talks, which include the two Koreas, the United States, Japan and Russia.
But Beijing says a real breakthrough can only be achieved if the US sits down and negotiates directly with North Korea - a key demand from Pyongyang.
Up to now though, Washington has refused to do that, preferring the multinational forum of the six party talks.
And that is the reality of the situation - both the US and China agree there is a problem - but they differ on the best way to solve it.
So Mr Hill will come repeat Washington's views on the issue and Chinese officials will once again make clear their position - but finding a way ahead won't be easy.