Asking Israel to reach a ceasefire with Hamas is "untenable", the UK's defence secretary has said, as the number of MPs calling for a cessation of hostilities grows.
Grant Shapps said Israel has "a right" to "go after" Hamas after its gunmen killed more than 1,400 Israelis on 7 October and abducted over 220 other people who are now being held hostage in Gaza.
Mr Shapps, who recently replaced Ben Wallace as defence secretary, took the same position as Rishi Sunak who said during Prime Minister's Questions on Wednesday that the "first and most important principle is that Israel has the right to defend itself under law".
However, Mr Sunak agreed that humanitarian aid had to get to civilians in Gaza and confirmed an RAF plane was on its way to the region with 21 tonnes of supplies, including medical equipment and water filters.
The Hamas-run health ministry has said at least 6,546 Palestinians have been killed in Israeli retaliatory strikes on Gaza.
Mr Shapps told the Politics Hub with Sophy Ridge that he agreed it was "very important that we can deliver that aid".
"The difference is we understand that Israel was attacked in a very brutal way by Hamas terrorists, butchering men, women and children ISIS-style," he said.
"I think to then ask Israel not to respond - or what you would describe as a ceasefire - I think is untenable.
"They have a right to go after those terrorists but it is the international humanitarian situation that a pause could assist with."
Mr Shapps went on to argue that if there had been a terrorist attack in the UK on the same scale that Israel had endured, "no one would expect us not to go after the perpetrators".
"To call for a ceasefire is to essentially say to Israel, having gone through that absolutely horrific terrorist attack just over two weeks ago, don't go after Hamas - and I don't think anyone thinks that would be right," he said.
"And so we can understand and appreciate under international law that Israel has the absolute right to do that.
"We also believe that it needs to be done in a proportionate way with international human rights law in place and that is very clear."
In the past few days, a number of MPs from across the political divide have called for a ceasefire, arguing that there was a "human responsibility" to protect civilians in the Gaza Strip who have had their water and power limited by Israel following the 7 October attack.
Speaking at this week's PMQs, the deputy leader of the SNP, Mhairi Black, pointed to warnings from the United Nations that some hospitals in Gaza City had less than 20 hours of fuel left and their electricity "runs out tonight".
She was joined by the leader of Northern Ireland's Social Democratic and Labour Party, Colum Eastwood, who asked: "As 1,400 Israelis and almost 6,000 Palestinians lay dying and dead, when will the prime minister say enough is enough? When will he call for a ceasefire?"
Labour shadow minister for equalities Yasmin Qureshi also echoed the calls for a truce and read out an email from one of her constituents with relatives in Gaza, which read: "My heart can't handle this. We are being massacred, relentlessly bombed, homes are being destroyed [and there is] no water, no food, no electricity."
In response to the calls from MPs, Mr Sunak urged people to remember that Israel had suffered "a shockingly brutal terrorist attack".
"Hamas is responsible for this conflict and Israel has the right to protect itself in line with international law as the UN charter makes clear."
The Labour Party has also resisted calls for a ceasefire but has signalled its support for a humanitarian pause in order to protect civilians.
The stance is the same as that adopted by US Secretary of State Antony Blinken, who told the UN Security Council on Tuesday that a humanitarian pause meant Israel "must take all possible precautions to avoid harm to civilians.
"It means food, water, medicine, and other essential humanitarian assistance must be able to flow into Gaza and to the people who need them."
In a live televised address on Wednesday evening, Israel's prime minister Benjamin Netanyahu said the country was "getting prepared" for a ground invasion, and troops have already "eliminated thousands of terrorists".
Asked whether he believed a ground invasion would fall under Israel's right to defend itself, Mr Shapps told Ridge: "As long as the people that they are going after are the Hamas terrorists, yes.
"The problem we have with Hamas is not just that they butchered and killed and raped those Israelis. It's that they also use their own Palestinian population - who are no friends of Hamas - as human shields, and they hide themselves amongst them.
"And so we understand and appreciate that it's a very difficult position for Israel to be in."