Kyiv’s SBU secret service said it had “conducted a new unique special operation and hit the Crimean Bridge for the third time – this time underwater”.

It published footage showing a blast coming out of the water and debris flying, along with a photo of some damage to the side of the bridge.

But the extent of the damage caused by the blast was unclear and the 19km bridge appeared to be in operation as normal this afternoon.

Russian state media reported it had been temporarily closed to traffic for around four hours earlier today.

The SBU said it had detonated more than 1,000kg of explosive material planted to one of the bridge’s underwater pillars.

Ukraine says the bridge is a legitimate target as it used to move troops and military equipment for its invasion.