BEIJING - China firmly opposes arms sales to Taiwan by any country and military ties with the island in any form, in light of the fact that the Taiwan question is China's internal affair, a military spokesperson said on Thursday.

Tan Kefei, spokesperson for the Ministry of National Defense, made the remarks in response to a plan of the US Department of Defense to sell weapons to Taiwan, which he said "sent very wrong signals" to separatist forces seeking "Taiwan independence."

The Chinese People's Liberation Army will take all necessary measures to crush any attempt to split Taiwan from China, and resolutely safeguard China's sovereignty and territorial integrity, Tan said.

The Chinese People's Liberation Army will take all necessary measures to crush any attempt to split Taiwan from China, and resolutely safeguard China's sovereignty and territorial integrity, a Chinese military spokesperson said

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A Chinese military spokesperson on Friday asked Japan to be discreet with its words and deeds on issues related to China's Taiwan region and the Diaoyu Islands.

Japan has ignored the basic norms of international relations, grossly interfered in China's internal affairs, deliberately hyped up the so-called "Chinese military threat," and made groundless accusations against China's legitimate maritime activities, said Tan Kefei.

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China has expressed its firm opposition and has lodged solemn representations with Japan, Tan added.

The Taiwan question is an internal affair of China, which allows no external interference, Tan said. The Diaoyu Islands and its affiliated islands are an inalienable part of China, and Chinese government ships' patrol and law enforcement activities there are lawful exercises regarding the country's sovereignty.

Tan said after the Second World War was over, the sovereignty of Diaoyu Islands was returned to China in line with international legal documents, including the Cairo Declaration and the Potsdam Proclamation.