In this file photo taken March 20, 1999

In this file photo taken March 20, 1999 shows a Chinese concrete fort and other structures in the Mischief Reef of the disputed Spratly Islands strategically located in the South China Sea. The structure that was built by China in 1995 in the Manila-claimed Mischief Reef raised tension with Philippines until an ASEAN consensus called for peaceful resolution of dispute. The Chinese embassy in Manila issued statement March 13, 2008 expressing concern over the growing controversy in the Philippines over a joint marine seismic study in the disputed Spratly islands. The Philippines and China signed an agreement for joint seismic studies in 2004 and this was later expanded to include Vietnam in 2005. The Spratlys, a chain of islands and atolls, are claimed by China, the Philippines, Brunei, Malaysia, Taiwan and Vietnam and are believed to be rich in oil and gas deposits. AFP PHOTO/ROMEO GACAD (Photo credit should read ROMEO GACAD/AFP via Getty Images)