US not planning air strikes on Iran, says Defence Secretary James Mattis

The United States is not planning air strikes on Iran and any such reports are fictitious, its Defence Secretary James Mattis has said.

"I have no idea where the Australian news people got that information. I'm confident it is not something that's being considered right now," he told reporters during a press gaggle.

He was responding to a news report in the Australian media that the US is planning an air strike on Iran.

Mattis trashed the report as "fiction".

Tensions between the US and Iran have been brewing for the past a few months since America announced withdrawal from the historic nuclear deal, signed during the previous Obama administration.

The deal was meant to curb Tehran's sensitive nuclear activities in return for lifting of crippling sanctions.

US President Donald Trump on Sunday had sent out a tweet to Iranian President Hassan Rouhani, saying "Never, ever threaten the united states again or you will suffer consequences the likes of which few throughout history have ever suffered before."

His tweet was apparently in response to comments Rouhani made that day cautioning Trump about the devastation of a US-Iran conflict. He had also warned Trump against interfering with his government.