Beijing has voiced "resolute opposition against infringement of China's sovereignty and security by any country in any form".
The Foreign Ministry spelled out China's stance after the Pentagon said that U.S.-Philippine joint patrols in the South China Sea will occur "regularly".
U.S. Defense Secretary Ash Carter confirmed on Thursday that the U.S. and the Philippines had already conducted such patrols.
The Foreign Ministry told China Daily, "The military exchanges ... should not target a third party, not to mention supporting some countries to provoke China's sovereignty and security, flaring regional contradictions and damaging regional peace and stability."
Beijing will follow developments, and general stability has been maintained in the South China Sea "through joint efforts by China and relevant countries", the ministry said
Carter reported the U.S. confirmation at a news conference with Philippine Defense Secretary Voltaire Gazmin in Manila. Carter met with the Philippine President Benigno Aquino earlier in the day.
Without quoting a source, Reuters reported the Pentagon saying that the first joint patrol took place in March and a second one took place earlier this month.
Carter started a visit to the Philippines on Wednesday during the annual U.S.-Philippine military drill that started on April 4. He will attend the closing ceremony on Friday.
Zhang Junshe, a senior researcher at the PLA Naval Military Studies Research Institute, said the U.S. will damage peace in the South China Sea by calling for joint patrols.
"When Washington calls China's behavior in the South China Sea 'coercive', the joint patrols have been a slap in the face. This is sheer coercion against China's peaceful development," Zhang said.
Carter said U.S. forces will be given access to more military bases in the Philippines than the five announced already.
The Ministry of National Defense said, "The U.S. Army has now returned, has reinforced its military presence in the Philippines and has given rise to militarization in the South China Sea region."
