VIENTIANE, Laos—China declared a diplomatic win at a regional summit after Southeast Asian leaders demurred on joining U.S.-led criticism of Beijing’s defiance against an international ruling that rejected China’s claims in the South China Sea.
Over a three-day summit that ended Thursday, leaders from the 10-member Association of Southeast Asian Nations instead reiterated calls for compliance with international law in handling territorial disputes with China, using a moderate tone that Beijing prefers.
Even the Philippines, which filed the arbitration case against China that yielded the ruling in July at a tribunal at The Hague, failed to mention the matter during a high-profile meeting on Thursday that included leaders from Asia and the U.S. In the closed-door meeting, U.S. President Barack Obama and Japan Prime Minister Shinzo Abe urged Beijing to comply with the verdict, which rejected Chinese claims to historic and economic rights across a wide swath of the South China Sea.
Asean’s reticence in discussing the ruling contrasted with Mr. Obama’s outspokenness on a legal case that Beijing has repeatedly denounced. Chinese diplomats seized on the divergence in rhetoric, claiming that the U.S. was trying to play up an issue that Asean has already moved on from.
“Only two countries are still sowing dissension, focusing on the South China Sea disputes and bringing up the arbitration case,” Chinese Vice Foreign Minister Liu Zhenmin told reporters after the summit. “This page on the arbitration has long been turned.”
Mr. Obama, speaking to reporters after Thursday’s meeting, continued to insist that the tribunal ruling is “legal and binding,” and said Asean leaders recognized its importance in declaring that Chinese claims to the disputed waters have no legal basis.
Washington has led calls from some Western and Asian governments for China to abide by the tribunal ruling. At a July gathering of regional foreign ministers, the U.S., Japan and Australia jointly urged China to abide by the tribunal ruling and show respect for international law.
Four Asean members—Malaysia, the Philippines, Vietnam and Brunei—claim territorial rights in the South China Sea. Those waters are home to rich fisheries and oil-and-gas reserves, carry some $5 trillion in trade each year, and is claimed almost in its entirety by Beijing.
Many Asean members, including those with claims in the strategic waters, are reluctant to antagonize China, which dwarves them economically and militarily and has been reclaiming land and constructing facilities in the contested Spratly Islands chain over the past two years.
“Asean nations realized that there is a need to seek practical solutions to manage disputes rather than unnecessarily inflaming tensions” by raising the tribunal as an issue, said Jia Qingguo, a professor of international studies at Peking University. “The U.S. would be disappointed that Asean didn’t follow its lead in discussing the arbitration ruling.”
Philippine President Rodrigo Duterte, who was attending his first international summit since taking office in June, was among those holding his tongue. Mr. Duterte had planned to mention the tribunal in his speech, according to a copy of his prepared remarks reviewed by The Wall Street Journal, but instead veered off-script to discuss human rights and other issues, according to Asean diplomats. Philippine Foreign Secretary Perfecto Yasay confirmed that Mr. Duterte gave an “impromptu speech” but didn’t give a reason.
Ernesto Abella, a spokesman for Mr. Duterte, earlier said that the Philippine president “doesn’t want to force issues” over the bilateral dispute with China. In August, Manila started preliminary discussions with Beijing on the possibility of bilateral negotiations over their territorial disputes. The talks are ongoing.
Mr. Duterte “knows that the arbitration ruling favors us, and so that’s why he’s willing to bide his time,” Mr. Abella told reporters on Wednesday. The spokesman also said that Manila continued to regard the ruling as “the basis” for any negotiation with Beijing.
—Carol E. Lee contributed to this article.