Updated March 18, 2017 09:17:36

Photo: After Japan and South Korea, China will be Mr Tillerson's most challenging stop. (AP: J. Scott Applewhite, file)

US Secretary of State Rex Tillerson has arrived in China for the final leg of his first official trip to Asia, and it is expected to be his most challenging and delicate stop to date.

On his two-day visit, Mr Tillerson will deal with a host of issues that threaten to derail the world's most important bilateral relationship.

Mr Tillerson will seek China's help in containing North Korea, and push China on its disputed claims over the South China Sea. Meanwhile, China will want a clarification on US threats of a possible trade war.

Mr Tillerson will also be preparing for a meeting between Chinese President Xi Jinping and US President Donald Trump, which is expected to occur early next month in the US.

Victor Gao, an advisor to the Chinese Government, said that would be a critical summit for the two superpowers.

"It will set the tone for the China-US relationship in the coming four years. It will also indicate how the two countries can benefit from co-operation with each other to solve the issues of the world," he said.

Mr Tillerson will seek China's support on his "new approach" to dealing with North Korea — although he is yet to provide specific details on what that strategy might be.

However, on Friday Mr Tillerson suggested it may be necessary to take pre-emptive military action against North Korea if the threat from their weapons program reaches a certain level.

Mr Tillerson said the "use of pre-emptive military force" would be an option in regard to North Korea. It is expected Mr Tillerson will reveal more about the US approach to North Korea during his talks with Mr Xi.

North Korea's launch of four ballistic missiles towards Japan has unnerved the US, and it has decided enough is enough, writes Philip Williams.

As North Korea's only traditional ally and biggest trading partner, America wants China to do more. China supplies about 90 per cent of the rough nation's trade and aid.

In return, China wants America to resume dialogue and stop deployment of its Terminal High Altitude Area Defence (THAAD) anti missile defence system in South Korea.

Mr Gao said THAAD was a hindrance and would not aid in the resolution of tensions.

"On the contrary, it actually will raise the stakes and become more destructive of any prospect of peace and stability on the Korean peninsula," he said.

On the South China Sea

Behind closed doors, it is expected Mr Tillerson will push back on the disputed South China Sea.

Last year, a United Nations tribunal ruled that China had no rights over the territory. At his confirmation hearing, Mr Tillerson told the US Senate that America should go further and stop China from having access to the islands it is building in the region.

But China's position will remain firm and clear: America has no role in the conflict and is not welcome in the waters.

"The best thing for the US to do is to urge negotiation and dialogue between China and the Philippines, which is taking place," Mr Gao said.

Mr Gao said he believed some individuals in the US administration were using the conflict in the South China Sea as an attempt to stop "China's peaceful rise".

The biggest economic risk Australia faces this year is a trade war between two of our biggest trading partners, writes David Taylor.

"There are people in the US who may want to resort to extreme means, including confrontation or conflict to achieve these objectives. This is a miscalculation and it won't be implemented," Mr Gao said.

"Doctor Henry Kissinger rightfully said, 'war is not an option between China and the US because the consequences will be destructive to US and China and also to the world'."

Mr Trump talked tough on China during his election campaign, but since his inauguration he has taken a hands-off approach and is yet to follow through on his promises to increase tariffs by 40 per cent.

But on the threats of a trade war, China will have a clear message for Mr Tillerson.

David Kelly from the Beijing-based China policy research institute said the Chinese would say something along the lines of:

"Don't think you will have to engage in a trade war, where at best you can get a draw, when if you play the game our way, it's a win-win."

No great clarification or resolution is expected on the issues in dispute. That is likely to happen when Mr Xi and Mr Trump meet next month.

Topics: government-and-politics, foreign-affairs, donald-trump, china, united-states

First posted March 18, 2017 07:12:24