The National People's Congress (NPC), China's top legislature, on Friday urged Vietnam to correct an erroneous maritime law it passed on Thursday.

The Foreign Affairs Committee of the NPC expressed its position concerning the recent passing of the Vietnamese Law of the Sea in a letter to the Committee on Foreign Affairs of the Vietnamese National Assembly.

The Vietnamese National Assembly passed the Vietnamese Law of the Sea to include China's Xisha Islands and Nansha Islands in the South China Sea within Vietnam's sovereignty and jurisdiction.

The NPC expressed its firm opposition to the move and urged the Vietnamese National Assembly "to correct the erroneous practice immediately."

"The move by the Vietnamese National Assembly is a serious violation of China's territorial sovereignty and is illegal and invalid. It violates the consensus reached by both leaders, as well as the principles of the Declaration on the Conduct of Parties in the South China Sea," the NPC Foreign Affairs Committee said in the letter.

"The NPC Foreign Affairs Committee hopes the Vietnamese National Assembly to honestly respect China's territorial sovereignty and correct the wrongful practice so as to safeguard the China-Vietnam comprehensive strategic cooperative partnership as well as the friendly relations between China's NPC and the Vietnamese National Assembly," the letter said.

The NPC also reaffirmed in the letter that China has indisputable sovereignty over the Xisha islands, Nansha Islands and their adjacent waters.