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

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

The United States, meanwhile, announced on Tuesday it was preparing new sanctions on Iran's missile and drone program after its weekend attack on Israel, and the European Union's foreign policy chief Josep Borrell signaled that the bloc would also levy new punitive measures.

Israeli military spokesman Rear Adm. 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 characterized the barrage as an act of self-defense following a deadly airstrike on its consulate in Syria, saying 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 Washington "is committed to Israel's security" but wants to prevent the conflict from spreading.

'New sanctions'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, a senior US official said.

US National Security Adviser Jake Sullivan said on Tuesday that Washington would "impose new sanctions targeting Iran, including its missile and drone program," as well as the Revolutionary Guards and the Iranian defense 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 behaviors."

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 deescalation in the aftermath of the weekend attack.

During a phone call with 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.

United Kingdom 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 voteThroughout, 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 Agence France-Presse (AFP).

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

Algeria, a nonpermanent 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 optionsIsrael was weighing its options after the Iranian drone and missile onslaught, which caused little damage as Israeli defenses 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.

Israel's military has vowed that 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 group's deadly October 7 attacks that sparked the conflict.

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