The United States fired a shot across China's bow a week ago by taking a tougher stance on maritime disputes in East Asia, a message Secretary of State John Kerry will amplify in Beijing this week.
The high tensions in Asia over Beijing's territorial claims in the East China and South China Seas will be near the top of Kerry's agenda when he meets senior Chinese officials on Friday. He will also discuss North Korea and climate change.
Kerry's top aide for East Asian and Pacific affairs, Assistant Secretary of State Danny Russel, drew a harder US line last week on a series of maritime disputes between China and its neighbors.
"It (Russel's testimony) certainly indicates a sharper tack in terms of the concerns we have and the steps we want China to take" on maritime disputes, said a senior State Department official. "Secretary Kerry will continue to press the Chinese to refrain from provocative actions and rhetoric and caution against the provocative nature of some of China's actions."
Russel faulted recent steps by China, including its November 23 declaration of an air defense zone (ADIZ) in an area of the East China Sea that includes islands at the center of a dispute with Japan, and suggested its South China Sea territorial claims that do not flow from land features are "fundamentally flawed".
China claims about 90% of the 3.5 million square km (1.35 million square miles) South China Sea, depicting what it sees as its area on maps with a so-called nine-dash line, looping far out over the sea from south China.
The United States is increasingly worried that China is trying to gain creeping control of the waters in the Asia-Pacific region, and Russel said its claims had "created uncertainty, insecurity and instability".
Kerry leaves Washington on Wednesday for a one-week trip to Seoul, Beijing, Jakarta and Abu Dhabi. Even though it will be Kerry's fifth visit to Asia since taking office a year ago, he has faced criticism for the time he has devoted to Middle East peace efforts rather than President Barack Obama's much vaunted policy of rebalancing the US military and economic focus toward Asia.
Doubts about this US commitment were highlighted in October when Obama called off plans to attend two summits in Asia because of a budget crisis at home, so the tougher stance signalled by Russel will be welcome in much of the region outside of China.
Analysts said Russel appeared to firmly blame China for the territorial disputes, warned against any attempt by the Chinese to declare a new ADIZ in the South China Sea and suggested that Chinese claims were not supported by international law.
"New model relationship"
China, in response to Russel's comments, accused the United States of undermining peace and development in the Asia-Pacific in a Foreign Ministry statement on Saturday that also said "these actions are not constructive".
Chinese officials described Kerry's trip as an "important" visit in which China would explore ways to strengthen ties and seek to deepen the "new model relationship" proposed when the US and Chinese presidents met in California last year. "We want to make that concept come alive," one Chinese official said on Tuesday.
Jonathan Pollack, an analyst with the Brookings Institution think tank in Washington, said the United States and China may have very different concepts of a "new model" of great power relationships, a phrase both have used.
"What Kerry will probably say is that the all too frequent kind of truculence that China is demonstrating in relation to a number of its neighbors is hardly the kind of confidence-builder that would leave the US assured of the ability to create that kind of relationship," Pollack said. "He will undoubtedly be explicit that the United States wants the relationship with China to be stable and productive in the longer term, but it's not going to be done at the cost of critical relationships with states that are China's near neighbors," he added.
Kerry met Japanese Foreign Minister Fumio Kishida in Washington on Friday and stressed the US commitment to defend Japan and stability in the Asia-Pacific region against the backdrop of Chinese territorial claims.
The United States flew B-52s through the Chinese air defense zone after it was declared last year. US officials have warned that a declaration of another zone in the South China Sea could result in changes to US military deployments in the region.
Jia Qingguo, associate dean of the School of International Studies at Peking University, said Beijing may try to reassure Kerry it does not want a conflict with Japan, even though it has not backed down over the East China Sea ADIZ.
"You have to stand up to the US when the so-called important interests of China are concerned," Jia said of the Foreign Ministry's angry response to Russel's comments, saying this reflected domestic politics as well as foreign policy. "But this does not mean that the two countries cannot pragmatically manage this kind of issue," he said.
The first stop on Kerry's trip is Seoul, where the main topic is likely to be North Korea, which over the weekend rescinded an invitation to a US diplomat to visit Pyongyang to discuss the fate of an imprisoned US missionary.
Kenneth Bae, a 45-year-old Korean-American, has been held for more than a year in North Korea after being sentenced to 15 years of hard labor on charges of trying to overthrow the state.
The United States has long sought to persuade China to use its economic leverage over the North, which has conducted three nuclear tests, to rein in its nuclear program.
From Seoul he travels on to Beijing and then to Jakarta, where he will give a speech on climate change in a country that is among the most vulnerable to the effects of climate change because it is an archipelago made up of more than 17,000 islands.