China warned France on Wednesday not to sell arms to neighbouring self-ruled Taiwan which is planning to buy weapons as part of an upgrade to a French-made warship fleet bought 30 years ago.

China says that Taiwan is part of "one China", and that this principle must be accepted by any country with which it has diplomatic relations. Arms sales to Taiwan are always highly sensitive and regularly prompt a strong reaction from Beijing.

Taiwan is mostly equipped with U.S.-made weapons, but in 1991 France sold Taiwan six Lafayette frigates, to China's anger. France also sold Taiwan 60 Mirage fighter jets in 1992.

Taiwan last month said it was seeking to buy equipment from France to upgrade the ships' missile interference system.

Speaking in Beijing, Chinese Foreign Ministry spokesman Zhao Lijian said China resolutely opposed any arms sales to Taiwan.

"We have already expressed our serious concern to France," he told a daily news briefing.

"We again urge the French side to abide by the one China principle and withdraw the arms sale plan to Taiwan to avoid harming Sino-French relations."

Taiwan's Defence Ministry said in response on Wednesday that the navy has said it is following related procurement regulations for the arm purchase to meet its "combat needs". It declined further comment.

Taiwan says it needs to upgrade its armed forces to deal with the growing threat from China, which has in recent months stepped up its military drills near the democratic island.

China describes Taiwan as its most sensitive and important territorial issue, and has never renounced the use of force to bring the island under its control. Taiwan has shown no interest in being ruled by autocratic China.