Donald Trump tweeted saying that If Iran wanted to fight it would be their official end. (File)

The standoff between Iran and the United States is a "clash of wills", a senior commander of Iran's powerful Revolutionary Guards said on Thursday, suggesting any enemy "adventurism" would meet a crushing response, Fars news agency reported.

Tensions have spiked between the two countries after Washington sent more military forces to the Middle East in a show of force against what US officials say are Iranian threats to its troops and interests in the region.

"The confrontation and face-off of the Islamic Republic of Iran and the malicious government of America is the arena for a clash of wills," Iran's armed forces chief of staff Major General Mohammad Baqeri said.

He pointed to a battle during the 1980-88 Iran-Iraq war where Iran was victorious and said the outcome could be a message that Iran will have a "hard, crushing and obliterating response" for any enemy "adventurism".

On Sunday, US President Donald Trump tweeted: "If Iran wants to fight, that will be the official end of Iran. Never threaten the United States again!"