Ruling seen as a victory for the Philippines, which filed the case before the tribunal at The Hague.
The Philippines has said that Beijing should respect an international tribunal’s ruling that rejected Chinese claims to most of the South China Sea, adding that it will raise the issue at a regional summit.
The Permanent Court of Arbitration in The Hague ruled on Tuesday that China’s claims to the resource-rich and strategically vital South China Sea had no legal basis.
China, which had boycotted the case brought by the Philippines, vowed to ignore the ruling, saying the UN-backed tribunal had no jurisdiction over the case and accused it of bias.
Beijing on Wednesday also raised the prospect of confrontation in the sea, and threatened to introduce an air-defence zone over the sea that would give its military authority over foreign aircraft.
On Friday, Philippine Foreign Secretary Perfecto Yasay will attend a two-day Asia-Europe summit, known as ASEM, in Mongolia along with Chinese Premier Li Keqiang.
“Secretary Yasay will discuss within the context of ASEM’s agenda the Philippines’ peaceful and rules-based approach on the South China Sea and the need for parties to respect the recent decision,” the foreign affairs department said in a statement, in the strongest response from the Philippines to the tribunal’s verdict.
China had said on Monday that the maritime dispute should not be included on the ASEM agenda, with assistant foreign minister Kong Xuanyou insisting the meeting was “not an appropriate venue” to discuss the issue.
The ASEM summit brings together nations from Asia and Europe, including other sea claimants Vietnam and Malaysia.
In his first comments immediately after the ruling, Yasay said the Philippines welcomed the decision but he did not urge China to respect or abide by it.
Yasay called then only for “all those concerned to exercise restraint and sobriety”.
Yasay will represent newly elected President Rodrigo Duterte at ASEM. The president has signalled the he wants to avoid a major diplomatic falling-out with China over the issue.
In his first cabinet meeting since being sworn into office on June 30, Duterte said that he would not “taunt or flaunt” a favourable ruling and aim for a “soft landing”.
The Philippines filed the legal challenge against China in 2013 under Duterte’s predecessor, Benigno Aquino.
China claims nearly all of the sea, even waters approaching the coasts of the Philippines and other Southeast Asian nations.
The ruling is expected to further increase tensions in the region, where China’s increased military assertiveness has spread concern among its smaller neighbours and is a point of confrontation with the US.
It could also spur Taiwan, Vietnam, Malaysia and Brunei, which also have overlapping claims in the South China Sea, to file similar claims.