"We are crushing the terror regime in Iran... with even greater vigour and with increasing force," Netanyahu said in a video released by his office.

"Yesterday, our pilots destroyed transport aircraft and dozens of helicopters at an Iranian Air Force base. Today they struck the railways and bridges used by the Revolutionary Guards."

In a statement, the Israeli military said it struck "eight bridge segments that were utilised by the Iranian terror regime's Armed Forces for transporting weapons and military equipment in several areas across Iran, including Tehran, Karaj, Tabriz, Kashan, and Qom".

Israeli military spokesman Brigadier General Effie Defrin said "air force pilots continue to deepen the damage to the Iranian terror regime".

"We eliminated several regime commanders last night and struck key infrastructure it used," he wrote in a post on X.

The announcement of the strikes came as US President Donald Trump warned "a whole civilisation will die" if a midnight deadline for a deal to open the Strait of Hormuz was not met.

Trump had warned that unless Tehran allowed free passage through the strategic oil chokepoint by midnight GMT, the United States would unleash what he called the "complete demolition" of Iran's critical infrastructure, including bridges and power plants.