China rejects Donald Trump's call to break away from Iran nuclear deal

China on Thursday rejected US President Donald Trump's call to "break away" from the Iranian nuclear deal and work for a new one, saying the agreement is a "hard won outcome" adopted by the UN and "all parties" should abide by it.

The nuclear deal called Joint Comprehensive Plan of Action (JCPOA) was reached between Iran and the P5+1, the permanent members of the UN Security Council - the US, the UK, Russia, France and China - plus Germany and the European Union in 2015.

President Trump has repeatedly criticised the nuclear deal as "very defective" and "foolish". He has already withdrawn from the agreement arguing that it does not meet the desired objective.

Trump said on Wednesday that "the time has come" for other nations to "break away from the remnants of the Iran deal, or JCPOA, and we must all work together toward making a deal with Iran that makes the world a safer and more peaceful place."

His call came amid the US and Iran tensions over the killing of Iranian General Qasem Soleimani in an American drone strike in Iraq on Friday. Iran retaliated by firing 22 missiles at US military bases in Iraq.

Commenting on Trump's remarks, Chinese Foreign Ministry spokesman Geng Shuang told the media here on Thursday that the root cause of tensions in the Middle East was the US' withdrawal from the nuclear deal.

"Now there is an escalation in the Middle East, the Iranian nuclear issue is facing severe challenges. The US unilaterally withdrew from JCPOA in ignorance of international law and obligations and obstructing the implementation by other parties. This (is the) root cause for the tensions," he said.

"This is also the primary circumstance parties should bear in mind while handling the Iranian nuclear issue. The JCPOA is the hard one outcome adopted by the UN and a pillar (of) stability and non-proliferation regime," he said.

"We urge all parties to abide by the deal (and) ease the tensions in Middle East. China will continue to stay in communication with other parties and work (to) realise the settlement for this end," he said.