China calls for maintaining peace and security as US president warns against reprisals by Iran

As US President Donald Trump warned on Saturday that Washington would strike multiple Iranian targets if Teheran retaliated for the US' targeted killing of Iran's top general, China vowed to play a constructive role in maintaining peace and security in the Middle East.

A day after announcing that the US military had killed Iranian military commander Qassem Soleimani and an Iraqi militia leader, Trump warned against possible reprisals from Iran, which has vowed to punish Americans "wherever they are in reach".

Trump said the US would hit 52 Iranian targets "very fast and very hard" if Teheran retaliates for the killing of Iran's top general, while a former US national security adviser said America is not safer after the attack.

China carried out a flurry of diplomatic efforts over the weekend in an attempt to reduce tension in the Gulf region of the Middle East, and officials and experts called for dialogue to reduce tension.

Iran's ambassador to the United Nations, Majid Takht Ravanchi, said in a letter to UN Secretary-General Antonio Guterres that Soleimani's killing was a "horrific assassination".

The killing was "an obvious example of state terrorism, and, as a criminal act, constitutes a gross violation of the fundamental principles of international law", Ravanchi wrote.

Susan Rice, the US national security adviser from 2013 to 2017, said Iran's response will likely be multifaceted and occur at unpredictable times and in multiple places.

If Trump reacts with additional force, the risk is great that the confrontation will "spiral into a wider military conflict", Rice wrote in an opinion piece published in The New York Times on Saturday. If he fails to react in kind, he will likely invite escalating Iranian aggression, she wrote.