French Defence Minister Florence Parly called on countries to abide by international law in the South China Sea, saying that France would persistently object to the creation of any claim to de facto sovereignty of the islands there.

In a veiled criticism of China's militarisation in the disputed waters, Ms Parly said at the Shangri-La Dialogue that the importance of these waterways to the economic security of states did not give them a right to bypass international maritime law.

She said in a speech at a session on regional security cooperation: "France is not part of territorial disputes in the area nor will it be, but we insist on two principles of the rules-based international order.

"Disputes should be resolved by legal means and negotiation, not by fait accompli, and freedom of navigation must be upheld."

But her comments that a South China Sea code of conduct should be legally binding - a sticking point with China - drew a pointed remark from a Chinese delegate as soon as the floor was open to questions.

China and Asean - which claimant states such as Malaysia, Indonesia, the Philippines and Vietnam are part of - are negotiating a code of conduct in the South China Sea, a move Ms Parly said France fully supports.

But she added: "It should be legally binding, comprehensive, effective and consistent with international law. We believe negotiations are the way to go."

Major-General Yao Yunzhu of China thanked Ms Parly for her speech but questioned her comment that the code of conduct should be legally binding. "France, to my knowledge, is not a negotiating state, so what kind of international law have you based your remarks on to make such demanding requests?"

Ms Parly replied that her comment had merely been an opinion.

In her speech, she also said countries should be very clear that fait accompli acts would not be accepted.

Security analysts have criticised China's actions in building military facilities on the disputed islands, saying this is done with the aim of leaving other countries no choice but to accept its de facto sovereignty.

Ms Parly highlighted France's freedom of navigation patrols in the South China Sea, saying it conducts them to uphold international law guaranteeing freedom of navigation. "Having said that, France is not a part of territorial disputes (in the South China Sea)and will never be, and France is not at all at war with China," she added.

France and Britain are cooperating on a maritime task group in the South China Sea, which includes British helicopters and ships.

Ms Parly said the convoy would call to port in Singapore next week and sail together "in certain areas".

Elaborating, she said: "I mean those areas where, at some point, a stern voice intrudes into the transponder and tells us to sail away from supposedly territorial waters.

"But our commander then calmly replies, that he will sail forth because these under international law are indeed international waters."

Ms Parly did not clarify if the scenario was a hypothetical one.

Separately, Reuters reported yesterday that the US is considering intensified naval patrols in the South China Sea, quoting officials and diplomats close to discussions.