Iran has unveiled an underground naval base capable of taking on "enemies big and small".
Footage broadcast on state TV shows a large number of speedboats lined up in what appears to be an underground tunnel.
It is reportedly part of a "secret" base built at a depth of 500m at an undisclosed location in the Gulf.
State TV showed Revolutionary Guards chief General Hossein Salami visiting the base with naval arm commander Rear Admiral Alireza Tangsiri.
It comes as Iranian leaders fear US president-elect Donald Trump, who will take over from Joe Biden following his inauguration in Washington later today, might empower Israeli Prime Minister Benjamin Netanyahu to strike Iran's nuclear sites.
In the footage, Gen Salami said the base was one of several built underground for vessels capable of launching long-range missiles and carrying out distant warfare.
"We assure the great nation of Iran that their young people are capable of coming out honourable and victorious from a battle on the seas against enemies big and small," he said.
State TV showed tunnels with long rows of what it said were a new version of Taregh-class radar-evading speedboats which can launch cruise missiles.
It also broadcast footage of the speedboats firing rockets at targets at sea.
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"The massive amount (of equipment) we saw today is a small portion of the power of the revolutionary guard's naval force, developed over the past years," Gen Salami said.
Iran has recently carried out military drills amid speculation of an attack by Israel, with the guard holding two air defence drills near key nuclear facilities in Natanz and Fordo.
Israel and Iran have traded strikes since the Hamas attacks on 7 October 2023, with neither side appearing to want a full-scale conflict.
The past year has seen Iranian proxy forces including in Gaza (Hamas), Lebanon (Hezbollah) and Yemen (Houthi rebels) attack Israeli and other Western assets in the region as part of the so-called Axis of Resistance in retaliation for the situation in Gaza - where, according to local authorities, more than 46,000 people are reported to have been killed in Israel's 15-month military campaign.
(c) Sky News 2025: Iran unveils underground naval base as it seeks to counter Israeli threat
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