The South China Sea is one of the world's freest and safest shipping lanes, Chinese Foreign Minister Wang Yi says, arguing that Beijing's control over the disputed waters is justified because it was the first to "discover" them.
China has come under fire from the US and its allies in recent months over its land reclamation activities in the South China Sea, through which $US5 trillion in ship-borne trade passes annually.
The US Navy has carried out freedom of navigation exercises, sailing near disputed islands to underscore its rights to operate in the seas.
Those patrols, and reports that China is deploying advanced missiles, fighters and radar equipment on islands there, have led Washington and Beijing to trade accusations of militarising the region.
The freedom of navigation does not equal the "freedom to run amok", Wang told his yearly news conference on Tuesday on the sidelines of China's annual parliament meeting.
"In fact, based on the joint efforts of China and other regional countries, the South China Sea is currently one of the safest and freest shipping lanes in the world," Wang said.
"China was the earliest to explore, name, develop and administer various South China Sea islands. Our ancestors worked diligently here for generations," Wang said.
"History will prove who is the visitor and who is the genuine host," he said, adding that China would "consider inviting" foreign journalists to islands under its control when the conditions are right.
China was neither the earliest country to deploy weapons to the South China Sea nor the country with the most weapons there, Wang added, without saying which country was.
Beijing claims almost all of the South China Sea, but Brunei, Malaysia, the Philippines, Taiwan and Vietnam have overlapping claims.
US Defense Secretary Ash Carter has warned of "specific consequences" if China takes "aggressive" action in the region.
He has said the US military was increasing deployments to the Asia-Pacific region and would spend $US425 million ($A568.60 million) through 2020 to pay for more exercises and training with countries in the region that were unnerved by China's actions.
Wang was also asked about the Philippines case against China in an arbitration court in The Hague on the South China Sea dispute. Manila has asked Beijing to respect the decision, which is expected in May.
China refuses to recognise the case and says all disputes should be resolved through bilateral talks.
