Iran said Monday its Foreign Minister Mohammad Javad Zarif will skip this week's World Economic Forum after organisers changed the event he had been planning to take part in.

The annual summit, which kicks off in the Swiss resort of Davos on Tuesday, has been overshadowed by escalating tensions between Iran and its arch foe the United States.

Zarif had been scheduled to attend the gathering after receiving a personal invitation, his ministry said.

"They changed the original programme they had for him, the programme that had been agreed upon, and came up with something else," said spokesman Abbas Mousavi.

"Either way, this trip unfortunately will not happen," he told a news conference in Tehran.

The annual gathering of global movers and shakers in the Swiss Alps begins on Tuesday and lasts four days.

But Zarif's absence removes any chance of a showdown with US President Donald Trump.

Tehran and Washington have been sworn enemies since the 1979 Islamic Revolution, but tensions have worsened since 2018 when Trump withdrew from the so-called Iran nuclear deal.

The two countries appeared to be on the brink of war after a US drone strike killed one of the Islamic republic's top military commanders, Qasem Soleimani, on January 3.

Iran hit back five days later by firing missiles at US troops stationed in neighbouring Iraq.

Hours later, when it had been braced for US retaliation, Iran's armed forces accidentally downed a Ukrainian airliner, killing all 176 people on board.