China has rejected an objection by Vietnam to a temporary fishing ban in the South China Sea imposed by Beijing, saying the move is aimed at protecting marine resources in an area under China's jurisdiction.
China last week announced the temporary ban on fishing in parts of the sea between May 16 and Aug 1.
"This is China's international responsibility and obligation," Foreign Ministry spokesman Hong Lei told reporters at a daily media briefing.
Vietnam, which also claims part of the area, said on Saturday in a statement posted on its Foreign Ministry website that the ban violates international law and Vietnam's sovereignty and jurisdiction.
Luo Yongkun, a researcher of Southeast Asian studies at the China Institutes of Contemporary International Relations, said, "People will agree that the move respects ... nature and is obviously good for the protection of fishery resources, thus benefiting countries in the region, including Vietnam.
"If Vietnam insists on fishing during this period, it will undermine not only the region's ecology but also stability."
China launched the annual fishing ban in 1999 "to promote sustainable development of the fishing industry in the South China Sea and to protect the fundamental interests of fishermen".
The quarrel between the two countries comes as they seek to mend ties hit by a row in May of last year when Vietnam protested over China setting up an oil rig near the Xisha Islands.
The rig's operations were disrupted by Vietnam, and it triggered anti-China demonstrations in the country that left at least four Chinese dead.
Vietnam's Communist Party chief Nguyen Phu Trong led a delegation to China last month - the highest-profile trip to China by a Vietnamese official since the conflict.
He and President Xi Jinping witnessed the signing of a host of agreements and pledged to tackle maritime friction properly.
Trong said both countries are carrying out reforms and need to improve co-operation and build a peaceful environment for development.
Economic ties between Vietnam and China, its top trading partner, have continued to grow. Trade volume saw double-digit growth last year, reaching $58 billion, according to Vietnam.
On Sunday, Chinese Defence Minister Chang Wanquan told his Vietnamese counterpart Phung Quang Thanh that both countries have "the wisdom and capability to achieve success in tackling maritime issues".
The meeting took place in Yunnan province.
Chinese and Vietnamese troops conducted a joint patrol in a border area on Sunday.
Zhuang Guotu, head of Xiamen University's School of International Relations, said: "The Vietnamese government should prevent its people from fishing in the area covered by the ban to safeguard the good atmosphere between the two nations."