The U.S. Pacific Fleet Commander has warned of a possible arms race in the disputed South China Sea which could engulf the region, as nations become increasingly tempted to use military force to settle territorial spats instead of international law, Reuters reports.

Commander Admiral Scott Swift urged nations, like China, to seek arbitration to settle maritime disputes.

"My concern is that after many decades of peace and prosperity, we may be seeing the leading edge of a return of "might makes it right" to the region," Swift said on Monday, December 14 in a speech in Hawaii, according to a copy seen by Reuters.

By resorting to military strength to impose territorial claims, nations, including China, risked sparking a military arms race that could engulf the region, he said.

"Claimants and non-claimants alike are transferring larger shares of national wealth to develop more capable naval forces beyond what is needed merely for self defense," Swift said.

China claims most of the South China Sea, through which more than $5 trillion of world trade ships every year, a fifth of it heading to and from U.S. ports.

Beijing is building seven man-made islands on reefs in the Spratly Islands, including a 3,000-metre-long (10,000-foot) airstrip on one of the sites, according to satellite imagery of the area.