China expressed on Tuesday firm opposition to armed attacks on peaceful nuclear facilities under International Atomic Energy Agency safeguards following reported attacks by the US and Israel on Iranian nuclear facilities.

"China advocates resolving the Iranian nuclear issue peacefully through political and diplomatic means and calls on all parties to remain calm and restrained to prevent further escalation," Foreign Ministry spokeswoman Mao Ning said at a regular news briefing.

According to media reports, recent US-Israeli strikes have attacked facilities in the Iranian cities of Ardakan, Bushehr and Khondab, including a heavy water reactor, a uranium enrichment facility and a nuclear plant.

Mao said attacks on peaceful nuclear facilities subject to IAEA safeguards severely undermine the authority of the Treaty on the Non-Proliferation of Nuclear Weapons, weaken efforts to uphold the international nuclear non-proliferation regime, and may bring serious consequences for regional peace, security and stability.