ASEAN and China are discussing setting up a "hotline" in case of an emergency regarding the territorial dispute over the South China Sea, a Philippine official said on Sunday.

The proposed hotline was discussed during a meeting of senior diplomats from China and ASEAN, the Association of Southeast Asian Nations, in Tianjin last week, said foreign department spokesman Charles Jose.

Jose, whose country is one of the most vocal in the simmering dispute over the flashpoint waters, said the matter had been referred back to a joint working group and was still far from fruition.

"Although this was agreed in principle as an early harvest measure, it needs thorough discussion," he said in a statement to AFP.

He stressed the hotline would not be unveiled at an upcoming meeting of ASEAN foreign ministers.

The Philippines and fellow ASEAN members Brunei, Malaysia and Vietnam have competing claims over the South China Sea along with China and Taiwan.

The dispute has grown increasingly tense in recent years with the Philippines at the forefront of accusing China of "bullying" in asserting its claim over the waters which are a crucial sea lane and fishing ground also believed to hold vast mineral resources.

In recent months, the Philippines has raised the alarm over China's land reclamation to turn outcroppings in the sea into artificial islands that can host military outposts.

ASEAN, which also includes Indonesia, Cambodia, Laos, Myanmar, Singapore and Thailand, has been pushing for the establishment of a "code of conduct" with China that would bind the rival claimants not to take actions that could spark conflict in the region.

Despite its appeals for unity, ASEAN members have diverging agendas, and the bloc has had difficulty taking a common stand on China which has close relationships with several members.