The EU urged all parties Friday to settle peacefully territorial disputes in the West Philippine Sea (South China Sea), where Washington has challenged Beijing's efforts to bolster its claims through an island-building program.

EU foreign affairs chief Federica Mogherini said the European Union was an "interested" party in a dispute pitting China against Taiwan, Vietnam, the Philippines, Brunei and Malaysia over control of a crucial seaway.

"We are committed to a maritime order based upon the principles of international law," Mogherini said in Luxembourg at the end of a two-day Asia-Europe (ASEM) foreign ministers meeting.

"We oppose any attempt to assert territorial or maritime claims through the use of intimidation, coercion, force or any unilateral action which could cause further friction," she told a closing press conference.

The meeting brought together the 28 EU member states plus more than 20 Asian countries, including emerging giants China and India, alongside their smaller neighbours in the Association of Southeast Asian Nations.

ASEAN has tried and failed for years to reach a modus vivendi with Beijing on the South China Sea where it claims most of the area, a hugely important transit point for global trade between Asia and Europe and believed to hold important oil reserves.

A meeting of Asia-Pacific defence ministers in Malaysia early this week failed again to agree wording on the issue after Washington sent the guided missile destroyer USS Lassen within 12 nautical miles, the accepted international limit, of one of the China-built formations.

Washington said the mission was conducted in international waters, unaffected by the Chinese land reclamation, and designed to reassert the principle of freedom of navigation on the high seas.

Beijing argued back that the USS Lassen mission was a threat to Chinese sovereignty.

Mogherini said the ASEM discussions on the issue were "very open ... very constructive."

"Some of the actors around the table have very different positions, conflicting positions I would say, but this did not prevent us from having a respectful and constructive exchange."

A statement issued by Mogherini as chair of the meeting said "ministers reaffirmed their commitment to maintaining peace."

"They agreed on the critical importance of refraining from the use or threat of force, of abstaining from unilateral actions and of resolving maritime disputes through peaceful means," it said.