Sir Keir Starmer has defended welcoming the Israeli president to Downing Street as MPs raised concerns about allowing him into the UK.
Sir Keir started Prime Minister's Questions (PMQs) by saying "however difficult, the UK must not walk away from a diplomatic solution" to the war in Gaza.
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"We will negotiate and we will strain every sinew, because that is the only way to get the hostages out, to get aid in and to stop the killing," he told MPs.
The PM said he will be "absolutely clear that we condemn Israel's action" in bombing Hamas leaders in Qatar, during his meeting with Israeli President Isaac Herzog on Wednesday afternoon.
His visit comes just a day after Israel carried out the strike in Qatar.
The PM added that it would be the "politics of students" not to meet Mr Herzog after the SNP's Westminster leader Stephen Flynn gave an impassioned speech against the Israeli president's visit.
Mr Flynn said: "Would he invite Vladimir Putin into No 10? Would he invite Benjamin Netanyahu into No 10?
"What does it say of this prime minister that he will harbour this man whilst children starve?"
Following Mr Herzog's visit to Number 10, the Israeli president said: "Britain and Israel are friends, but among friends there are sometimes disagreements."
He said he "made clear" the UK's intention to recognise a Palestinian state would "in no way help bring the hostages home, help the Palestinians, or help bring an end to the conflict" - but would instead "embolden extremists".
The president also told Sir Keir it was "dangerous" to "echo Hamas's propaganda campaign of starvation in Gaza".
MPs question Herzog visit
Dozens of MPs from all parties, including Labour, questioned the legal standing of Sir Keir welcoming Mr Herzog.
The Israeli president previously said there are "no innocent civilians in Gaza" and "it is an entire nation that is responsible".
He was also pictured signing an artillery shell before it was fired towards Gaza in December.
The prime minister's spokesman said the attack in Qatar is a "clearly unacceptable act" and said it "of course" would be one of the subjects raised with Mr Herzog.
He added Sir Keir will be "clear" with Mr Herzog about the risk of Israel escalating its actions.
Handcuffs not handshakes
New Green Party leader Zack Polanski called for "handcuffs not handshakes" as he said Scotland Yard's war crimes unit should be waiting inside Number 10 to handcuff Mr Herzog "and take him away for questioning".
Mr Polanski, who won the Greens leadership election last week and is Jewish, accused Mr Herzog of being "complicit while the Israeli government has engaged in committing genocide in Gaza".
Israel has continually denied it is carrying out a genocide in Gaza, but last week, the world's leading association of genocide scholars declared it is. Earlier this week, the UK government concluded Israel is not committing genocide in Gaza.
Herzog is a conduit
The Liberal Democrats tabled an urgent question following PMQs, calling on the foreign secretary to make a statement on the implications of Israel's strike in Qatar.
Foreign Office minister Hamish Falconer took to the despatch box to defend Mr Herzog's visit, saying: "President Herzog is on a private visit to the UK.
"He is not a functional part of the government; he is an important conduit to raise these concerns."
Mr Falconer said the UK is supporting a motion for an emergency meeting of the UN Security Council on Wednesday evening and revealed Foreign Secretary Yvette Cooper is speaking to the E3 (UK, France and Germany) and G7 allies, including the US about Israel's attack on Qatar.
He added that Ms Cooper met Mr Herzog in the morning and "amongst other things" asked him to ensure greater support from the Israeli government to get children with injuries and students out of Gaza.
As PMQs was taking place, union members at the Trades Union Congress (TUC) conference unanimously passed a motion to oppose Mr Herzog's visit.
On Tuesday evening, 60 cross-party MPs and Lords gathered outside parliament to condemn Mr Herzog's visit after they sent a letter to Sir Keir asking what legal advice the government has received about Mr Herzog's visit and whether his entry to the UK "is compatible with our obligations under the Genocide Convention".
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