"That's about our rough estimate right now, approximately $320 million," Deputy Pentagon Press Secretary Sabrina Singh told journalists, adding: "That's an initial cost for the temporary pier."

The Pentagon announced Thursday that construction of the pier had begun, saying it should be operational in early May.

At that point, aid will be transported via commercial vessels to a floating platform miles off the Gaza coast, where it will be transferred to smaller vessels, brought to the pier and taken to land by truck for distribution.

Plans for the pier were first announced by US President Joe Biden in early March as Israel held up deliveries of assistance by ground.

The humanitarian situation in Gaza -- which has been devastated by more than six months of Israeli operations against Hamas -- remains dire, with a senior US administration official saying last week that the territory's entire population of 2.2 million people is facing food insecurity.

Hamas's October 7 attack on southern Israel that triggered the war resulted in the deaths of about 1,170 people, mostly civilians, according to an AFP tally of Israeli official figures.

Israel's retaliatory offensive has killed at least 34,488 people in Gaza, mostly women and children, according to the health ministry in the Hamas-run territory.