The launches came a day after the Guards struck a mock-up of a US aircraft carrier with volleys of missiles near the Strait of Hormuz, a vital shipping lane for a fifth of world oil output.

The Iranian manoeuvres were staged amid heightened tensions between Iran and its decades-old arch enemy the United States.

Iranian state television broadcast aerial footage of the latest daylight exercises in the desert showing bursts of flames, smoke and dust before what appeared to be four projectiles climbed into the sky.

The Islamic Revolutionary Guard Corps (IRGC) said in a statement on their Sepahnews website that it was "the first time in the world" that such an exercise had been carried out.

The statement did not elaborate on the claim or provide any of the missiles' specifications.

It hailed "the successful launch of ballistic missiles from the depths of the Earth in a completely camouflaged way" as an "important achievement that could pose serious challenges to enemy intelligence organisations".

The Guards said they also released bombs from Sukhoi Su-22 fighter-bombers to target predetermined positions on Bani Farur Island in Iran's territorial waters.

"These launches were carried out without the platform and usual equipment," IRGC aerospace chief Brigadier General Amirali Hajizadeh said on state television.

"The buried missiles suddenly tear through the ground and hit their targets with precision," he said, adding again that this happened "for the first time in the world".

- 'Heightened alert status' -

Iran had also fired ballistic missiles during the naval exercise on Tuesday, according to a spokesman for the Revolutionary Guards.

"Some surprise equipment and weapons were used, such as long-range ballistic missiles capable of striking offensive floating targets in the distance," General Abbas Nilforoushan said Tuesday.

US Central Command (CENTCOM) said Tuesday that Iranian forces had "at approximately 5:30 a.m. local time... launched several ballistic missiles from Iran to the Southern Arabian Gulf".

It said two military bases, al-Udeid in Qatar and Al-Dhafra in the UAE, had "out of an abundance of caution... enacted a heightened alert status" before the all-clear was declared shortly afterwards.

Tensions have escalated between Tehran and Washington since US President Donald Trump unilaterally withdrew in 2018 from a landmark nuclear deal between Iran and world powers.

The sworn enemies have come to the brink of direct confrontation twice since June 2019, when the Guards shot down a US drone in the Gulf.

Their animosity deepened after Iran's most prominent general, Qasem Soleimani, was killed in a US drone strike near Baghdad airport in January.

Days later, Iran launched a volley of missiles at Iraqi bases housing US and other coalition troops.

The US said they had not taken any lives, only causing "minimal damage", and Trump refrained from any further military response.