"The two leaders began discussing the horrific scenes in Gaza and agreed on the need for urgent action to end the suffering that has reached unprecedented levels," the office added in a statement issued after Starmer and Trump met in Scotland.
"Humanitarian aid must be allowed in on a large scale and quickly. We declared our commitment to working together to end the misery and hunger, and to continue pressing for the immediate release of the remaining hostages," the statement read.
The two leaders also renewed their call for an immediate ceasefire to pave the way for peace in the region.
With US support, Israel is waging a war of genocide in Gaza, including killing, starvation, destruction, and forced displacement, ignoring all international calls and orders from the International Court of Justice to halt the campaign.
The US-backed genocide left more than 204,000 Palestinians dead or wounded, most of them children and women, and more than 9,000 missing, in addition to hundreds of thousands of displaced persons and a famine that claimed the lives of many.