Washington has signed a new defence agreement with the Philippines as US President Barack Obama landed in Manila as part of an Asia tour aiming to reassure allies wary of a rising China while avoiding antagonising Beijing.
The ten-year deal, signed by Philippine's defence minister Voltaire Gazmin and US ambassador Philip Goldberg on Monday, will not allow Washington to establish a permanent base in the Philippines or bring in nuclear weapons to the country.
However, it will allow more of the high-profile war games that are regularly conducted by the long-time allies and for some US military hardware to be stationed on Filipino soil, as part of a US rebalancing of military power towards rising Asia, the AFP news agency reported.
Anti-China sentiments run high in the Philippines, which is locked in a showdown with Beijing over disputed atolls in the South China Sea, part of a proliferation of maritime hotspots that has stoked Asian tensions.
The Philippines has accused China of becoming increasingly aggressive in staking its claims to the sea, and has called on the US for greater military as well as diplomatic support.
During an Asian tour that has taken him to Japan, South Korea and Malaysia, Obama has repeatedly warned that small nations should not be bullied by larger ones, a clear reference to China's increasingly sharp geopolitical elbows.
"Disputes need to be resolved peacefully, without intimidation or coercion, and all nations must abide by international rules and international norms," Obama said in Malaysia on Sunday.
Opening his trip, Obama made clear that US defence treaties with Japan did cover disputed islands long administered by Tokyo in the East China Sea, which are known as the Senkakus in Japan and Diaoyus in China.
As for Philippines' territorial disputes with China in the South China Sea over the Second Thomas Shoal, US officials have not been so specific over perceptions of their obligations towards Manila on territorial disputes.
It is clear, however, they do not believe they are covered by the American Mutual Defence Treaty with the Philippines.
"With respect to some of the difficult territorial issues that are being worked through, it is hard to speculate on those because they involve hypothetical situations in the South China Sea," said US deputy national security adviser Ben Rhodes.
The Philippines hosted two of the largest overseas US military bases until 1992, when Manila voted to end their lease at a time of growing anti-US sentiment.
With rising regional disquiet over the implications of China's rise, the Philippines has sought greater military ties with Washington in recent years.