Israel and Iran traded threats after Tehran's first-ever direct attack on its arch-foe sharply heightened tensions in a region already on edge after six months of war in Gaza.

The war in the besieged territory and its soaring civilian toll have revived the push for a two-state solution, with the UN Security Council preparing to vote Thursday on full United Nations membership for a Palestinian state, according to diplomatic sources.

The United States, meanwhile, announced Tuesday that it was preparing new sanctions on Iran's missile and drone programme after its weekend attack on Israel, and the EU's foreign policy chief signalled the bloc would levy new punitive measures as well.

Israeli military spokesman Rear Admiral Daniel Hagari said Iran would not get off "scot-free" after Tehran and its allies launched a barrage of more than 300 missiles, drones and rockets at Israel.

"We cannot stand still from this kind of aggression," Hagari said, a day after Israel's military chief vowed there would be "a response" to Iran's attack.

Iran has characterised the barrage as an act of self-defence following a deadly air strike on its consulate in Syria, saying that it would consider the matter "concluded" unless Israel retaliated.

Iran's President Ebrahim Raisi warned that "the slightest action against Iran's interests will definitely be met with a severe, extensive and painful response".

US President Joe Biden has stressed that "the United States is committed to Israel's security" but wants to prevent the conflict from spreading.

Washington, Israel's top ally and arms supplier, has made clear it will not join Israel in any retaliatory attack on their common adversary Iran, according to a senior US official.

US National Security Advisor Jake Sullivan said Tuesday that Washington would "impose new sanctions targeting Iran, including its missile and drone programme", as well as the Revolutionary Guards and the Iranian defence ministry, in the coming days.

The measures, he said in a statement, would help to "contain and degrade Iran's military capacity and effectiveness and confront the full range of its problematic behaviours".

EU foreign policy chief Josep Borrell said Brussels was also working on expanding sanctions against Iran, particularly against its supplies of weaponry -- including drones -- to Russia and proxy groups around the Middle East.

World leaders have urged restraint and de-escalation in the aftermath of the weekend's attack.

During a phone call with Iran's Raisi, Russian President Vladimir Putin called on both sides to "prevent a new round of confrontation fraught with catastrophic consequences for the entire region", the Kremlin said.

UK Prime Minister Rishi Sunak warned his Israeli counterpart Benjamin Netanyahu against "significant escalation" and said now was a moment for "calm heads to prevail".

- Palestinian UN vote -

Throughout, Israel has kept bombing targets in Gaza, the Hamas-ruled Palestinian territory that has been largely devastated by more than six months of war and a siege on its 2.4 million people.

Against the backdrop of the grinding conflict, the Security Council is expected to take up the matter of full Palestinian UN membership on Thursday, several diplomatic sources told AFP.

The Palestinians this month formally revived an application first made to the world body in 2011, though the veto-wielding United States has repeatedly expressed opposition to the proposal.

Algeria, a non-permanent Security Council member, has drafted the resolution recommending full Palestinian membership.

The Security Council in March adopted a resolution calling for a ceasefire in Gaza, but to little effect, with negotiations toward a truce stalled after the latest proposal did not get Hamas approval.

- Weighing options -

Israel was weighing its options after the Iranian drone and missile onslaught, which caused little damage as Israeli defences intercepted most projectiles, with help from US, British and French forces, as well as regional allies.

It remained unclear when Israel might strike back and whether it would target Iran directly or attack its interests or allies abroad in places such as Lebanon, Syria, Iraq and Yemen.

Iran-backed Hezbollah, which has been trading regular cross-border fire with Israel since October, claimed an attack with two explosive drones near a northern Israeli town on Tuesday that the local council said wounded three people.

Also on Tuesday, an Israeli strike killed a local Hezbollah commander in southern Lebanon, a source close to the group and the Israeli military said. Hezbollah later said two more of its fighters had been killed, while its ally the Amal movement announced one dead.

Hezbollah said it launched rockets at Israel in response.

Israel's military has vowed the tensions with Iran will not distract it from the ongoing war in Gaza, where it aims to destroy Hamas and bring home the hostages taken during the October 7 Hamas attack that sparked the conflict.

On Tuesday, Netanyahu told new army recruits that Israeli forces were fighting Hamas "without mercy".

The group's October 7 attack on Israel resulted in the deaths of 1,170 people, mostly civilians, according to Israeli figures.

The militants also took about 250 hostages, of whom Israel estimates 129 remain in Gaza, including 34 who are presumed dead.

Israel's retaliatory offensive has killed at least 33,843 people in Gaza, mostly women and children, according to the health ministry in the Hamas-run territory.

- 'No change' in Gaza aid -

Israel has faced growing global opposition to the relentless fighting, which has triggered a dire humanitarian crisis in Gaza.

The United Nations agency for Palestinian refugees, UNRWA, said there had been "no significant change" in the amount of humanitarian relief entering Gaza, even after the International Court of Justice ordered Israel to allow in more aid.

The United Nations said it would launch an appeal on Wednesday for $2.8 billion to help Gaza, as well as the occupied West Bank. Its humanitarian office, OCHA, said it had planned to raise $4 billion, but slashed the target due to the difficulty of getting aid to Gazans.

Also on Tuesday, UN Women said that six months into the war 10,000 Palestinian women had been killed, including 6,000 mothers. More than 19,000 children had been orphaned, the agency said.

With many in the territory going hungry, Wissam Dawad was one of hundreds who waited in line for hours to get bread from a newly reopened bakery in Gaza City.

"When Israel prevented us from getting flour, we started eating corn and barley, until it reached the point where we had to eat some animal feed," he told AFP.