CHINA should expect a more robust involvement from the United States regarding territorial disputes in the South China Sea, analysts say, citing recent criticisms by senior American diplomats and top military brass.
Some point to how the US, which has long stressed that it does not take sides in the disputes, appears to have done exactly that when it rejected a historical nine-dash line that Beijing has been using to justify its claims over nearly 90 per cent of the sea.
Referring to US Assistant Secretary of State for East Asia and Pacific Affairs Daniel Russel's remarks last week that "any use of the 'nine-dash line' by China to claim maritime rights not based on claimed land features would be inconsistent with international law", Major-General Ji Mingkui said they were clear proof that the US is now taking a stand in the South China Sea disputes.
"The intention is to create conflict between China and its neighbours and lead them to a showdown with China," the National Defence University lecturer wrote in a commentary on Sunday.
Others noted the increased seniority and frequency of US officials lambasting China over its handling of territorial disputes as an unusual phenomenon that hints of a tougher US stand to come.
Top officials such as Secretary of State John Kerry and Pacific Command chief Samuel Locklear have criticised China's Air Defence Identification Zone in the East China Sea, which includes the Diaoyu/Senkaku islands also claimed by Japan.
US officials have warned China not to set up a similar zone in the South China Sea where it faces overlapping claims from Vietnam, the Philippines, Malaysia, Brunei and Taiwan.
Guangzhou-based Asean expert Zhang Mingliang noted US officials tend to make comments about the South China Sea disputes around July when they attend meetings between Asean and dialogue partners which include the US and Japan.
"We can expect to see a more proactive and pre-emptive intervention from the US over the disputes," Professor Zhang of Jinan University told The Straits Times.
Chinese observers think the US is taking a tougher stand to ease any doubts its allies like the Philippines may have about Washington's commitment, especially after President Barack Obama cancelled visits last year, and to test the waters ahead of visits to Asia by Mr Kerry this week and by Mr Obama some time in April.
Prof Zhang believes the US could follow up with actions such as holding more military exercises with other claimants like Vietnam and the Philippines, and offering more military assistance.
He added the US may also help speed up the resolution of a case Manila has brought before a United Nations tribunal, challenging the nine-dash line as having no basis under international law.
The U-shaped line, which extends up to 1,800km from the Chinese mainland, stirred controversy in 2009 when Beijing officially used it to justify its claims over the South China Sea in a map submitted to the UN.
Since then, China has become increasingly assertive in the area, stepping up military exercises, relocating its people to a disputed island, and issuing new rules requiring foreign fishing boats to seek permission before entering its waters.
Chinese international affairs commentator Xiao An saw Mr Russel's comments as de facto US support for the Philippines' land-based sovereignty claims and a dismissal of historical claims by China.
In anticipation of a tougher US stance, China would have to persevere with its strategy regarding the South China Sea, which includes promoting economic development with Asean states and supporting talks on a proposed Code of Conduct, Mr Xiao wrote last Saturday.
"China must spell out clearly what can be discussed and what can be done at a multi-lateral platform, and also our bottom line," he added.
Peking University analyst Zha Daojiong said the US government must thus clarify "its basic stance" over the South China Sea, in light of Mr Russel's comments.
"Some in China view the US as essentially saying this: whatever claim a South-east Asian state puts forward in relation to the South China Sea receives automatic American backing; whatever claim China has is automatically rejected by the US," he told The Straits Times.
"If that is the case, comments like those by Mr Russel can serve only to harden Chinese resolve."