For the first time, the UK's foreign secretary, David Lammy, accused Israel of "breaching international law" during a House of Commons debate on Monday afternoon.
His comments came before Israel began renewed strikes on targets in Gaza later on Monday night.
Lammy condemned Israel's halting of aid into the Strip - as a means of pressuring Hamas to return the remaining hostages - calling it "appalling and unacceptable" and adding that aid should never be used as a political tool.
Responding to a question from MP Rupa Huq about the aid blockage during Ramadan, Lammy said, "This is a breach of international law."
"While Israel quite rightly must defend its own regional security," he said, "it has been 15 days since aid got into Gaza [which is] unacceptable, hugely alarming, and very worrying. We would urge Israel to get back to the amount of trucks from before so that Palestinians can get the necessary humanitarian support that they need at this time."
Lammy addressed the room with details of the recent G7 meeting, in which members discussed conflict in Ukraine, Israel, the DRC, and others.
He said the "G7 united in support for the fragile ceasefire in Gaza, the release of all hostages, and unhindered humanitarian aid into Gaza."
He also reiterated prior statements that Hamas can have no role in Gaza's future.
British chancellor: UK will use diplomatic influence
Although Lammy's comments came before the start of IAF strikes on Monday night, his colleague - Labour MP Pat McFadden - told Sky News on Tuesday morning that "the UK government will use the diplomatic influence we have to try to get that ceasefire restored as soon as possible."
McFadden serves as Chancellor of the Duchy of Lancaster, making him the highest-ranking minister in the Cabinet Office after the prime minister.
In response to a question by the Sky News anchor as to whether the UK holds sway, given the US had approved of the attack before it began, McFadden said, "I think the UK has diplomatic influence. I still think that the UK's diplomatic voice counts in the world."
Asked whether the UK holds the position that Israel has breached international law, McFadden responded, "We never want to see the denial of essential supplies like food or electricity or water to a civilian population."
He added that David Lammy "speaks for the government" on that matter.
He, however, iterated that "Israel has a right to defend itself" and that the UK will "always defend that right."