"Not Looking To Start War With Iran, But Prepared To Finish One": US

US Defense Secretary Mark Esper said on Tuesday the United States wants to de-escalate tensions with Iran, but the country is ready to finish any war that could be started.

"We are not looking to start a war with Iran, but we are prepared to finish one," he said. "What we'd like to see is the situation de-escalated."

The U.S. drone strike on Friday that killed Iranian military commander Qassem Soleimani has sharply escalated tensions with Iran, raising fears of all-out conflict. Washington says it killed Soleimani in self-defence, aiming to disrupt his plans to attack U.S. personnel and interests.

Esper defended the intelligence signalling an "imminent threat" from Soleimani that he and other senior US officials have cited to justify the strike, saying it was persuasive.

"The threat was being orchestrated by Soleimani," Esper said. "I think it was only a matter of days, certainly no more than weeks" before an attack.

Esper suggested on Monday that the US military would not violate the laws of armed conflict by striking Iranian cultural sites, a move threatened by US President Donald Trump.

Asked about the issue again on Tuesday, Esper said he was confident that Trump "will only give us legal orders."

"We do not violate the laws of armed conflict," Esper said.

Targeting cultural sites with military action is considered a war crime under international law, including a UN Security Council resolution supported by the Trump administration in 2017 and the 1954 Hague Convention for the Protection of Cultural Property.