The British, French and Canadian leaders issued a joint statement on May 19 in which they condemned Israel's "egregious actions" in Gaza, warning that concrete action could follow if it does not stop its military offensive. They said an 11-week blockade on humanitarian aid reaching the territory had led to an "intolerable" level of human suffering.

Israel's prime minister, Benjamin Netanyahu - who the International Criminal Court (ICC) alleges is responsible for war crimes in Gaza - responded angrily. He accused the leaders in London, Ottawa and Paris of offering Hamas a "huge prize" for its October 7 attack on Israel.

This drew a rebuttal from the British foreign secretary, David Lammy, who declared that "opposing the expansion of a war that's killed thousands of children is not rewarding Hamas". So, what action can Israel's western allies take over its offensive in Gaza?

The most realistic option is probably the recognition of Palestinian statehood. The Netanyahu government has expressed fierce opposition to the establishment of a Palestinian state, saying recently it would be a "win for terrorism".

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But this recognition would send a strong message of support for a two-state solution, which most of the world has long seen as the only way to end the Palestinian-Israeli conflict. And the UK, along with Canada, has said it is joining a French initiative to recognise Palestine as a state at a June conference in New York, organised to advance a two-state solution.

By doing so, the UK, France and Canada would join 160 states that already recognise Palestine. These include 11 states in the EU: Bulgaria, Cyprus, the Czech Republic, Hungary, Ireland, Poland, Romania, Slovakia, Slovenia, Spain and Sweden.

Another option is for western states to stop selling arms to Israel. France has done this already. And the British government partially suspended arms exports to Israel in September 2024 over concerns they could be used unlawfully in Gaza.

However, in the three months that followed, the government reportedly approved US$169 million (Pound 126 million) worth of military equipment to Israel. This is more than the total amount it approved between 2020 and 2023.

The UK maintains that its "exports of military goods to Israel are low", and the same is true for Canada. The UK and Canada together provide less than 1% of the annual value of Israel's military imports. But a full suspension would be a major political statement, demonstrating diminishing international support for Israel's military offensive in Gaza.

For a total ban to have any effect on the Israeli military's operations, it needs to be complemented by similar action from more significant arms providers. Germany, for instance, accounted for 30% of Israel's arms imports between 2019 and 2023.

The UK and Canada are also part of the global F-35 jet fighter programme, with the UK alone supplying 15% of the value of each jet. F-35 jets play a key role in Israel's military operations in Gaza. But stopping British-made parts for F-35s from being supplied to Israel is unlikely.

It would involve pulling out of the entire programme, which the government says is crucial for international security. However, given the High Court is hearing a case that alleges the sale of components for F-35s indirectly to Israel breaks domestic and international law, its stance could change.

Western countries could also suspend their trade with Israel. The EU accounts for almost 30% of Israeli exports, with a similar amount of Israeli imports coming from the EU. The UK is the 11th-largest importer of Israeli goods.

This option would have a significant impact on Israel's economy, and is being considered by both the UK and EU. On May 20, Lammy announced the suspension of negotiations over a new free trade deal between the UK and Israel. And the EU has said it will review its trade association deal with Israel, after 17 of the bloc's 27 foreign ministers backed the move.

A complete suspension of the EU's trade agreement with Israel would require unanimity, so it is unlikely. But a partial suspension is possible, as this would only require at least 55% of member states to vote in favour.

One more option is the expansion - and coordination - of efforts to sanction Israeli nationals who promote violence against Palestinians. In 2024, France, Canada and the EU imposed financial sanctions and travel bans against extremist Israeli settlers who had been found guilty of using violence against Palestinian civilians in the West Bank.

The UK has now taken a similar approach, introducing sanctions on several individuals and entities involved in the Israeli settler movement. This includes prominent Israeli settler Daniella Weiss, who featured in Louis Theroux's recent documentary, The Settlers. Weiss has dismissed the sanctions, saying they will not affect her or the broader settler movement.

Britain's government is also reportedly considering sanctions against Israel's finance minister, Bezalel Smotrich, and national security minister Itamar Ben-Gvir. Lammy referred to Smotrich's recent comments that the Israeli military offensive will be "destroying everything that's left" of Gaza as "monstrous".

Sanctions could, in theory, be complemented by bans on the import of goods from Israeli settlements. Israel's finance ministry says that 2.5% of the country's agricultural exports and 1.5% of industrial exports to the EU originate in settlements.

This type of ban would be difficult for France to introduce due to EU law, but it might not be impossible. Ireland is also trying to ban the trade of goods from such settlements.

Above all, Israel's allies should step up their efforts to respect international law. In November 2024, the ICC issued an arrest warrant for Netanyahu over alleged war crimes relating to the Gaza war.

The UK and Canada have said they would arrest Netanyahu if he travels to either country - and they could apply pressure on France to join them. France has not said whether it would arrest Netanyahu if he sets foot on French territory.

The humanitarian situation in Gaza is likely to worsen over the coming weeks and months. If Israel's western allies want to use their influence to force the Israeli government to end the conflict, now is the time.