Iran will respond firmly to any U.S. threat against it, the semi-official Tasnim news agency reported on Saturday, citing foreign ministry spokesman Abbas Mousavi.

"We will not allow any violation against Iran's borders. Iran will firmly confront any aggression or threat by America," he was quoted as saying.

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General: Iran gave 2 warnings before downing U.S. drone

What comes next as tensions mount high between U.S., Iran?

U.S. President Donald Trump approved military strikes on Friday against Iran in retaliation but pulled back the order later "because it would have been a disproportionate response."

Iranian officials told reporters on Friday that Tehran had received a message from Trump warning that a U.S. attack on Iran was imminent but that he was against war and wanted to talk.

Iran said late Friday that it gave two warnings before downing a U.S. reconnaissance drone over the Gulf of Oman, according to the commander of the aerospace arm of the country's elite Revolutionary Guards.

Tension between Tehran and Washington has spiked since Thursday when an Iranian missile destroyed a U.S. Global Hawk surveillance drone. Tehran said the drone was shot down over its territory and Washington said it occurred in international airspace.

(With input from Reuters)

(Cover: General Amir Ali Hajizadeh (C), Iran's head of the Revolutionary Guard's aerospace division, speaks to media next to debris from a downed U.S. drone reportedly recovered within Iran's territorial waters and put on display by the Revolutionary Guard in the capital Tehran, June 21, 2019. /VCG Photo)