Civilians are bearing the brunt of a "truly catastrophic" situation in Lebanon, a senior UN official said, urging respect for the rules of war nearly two weeks since Israel launched a major offensive against the armed group Hezbollah.

With around 1 million people in Lebanon impacted, Imran Riza, UN Resident and Humanitarian Coordinator, said the pace of displacement since Sept. 23 had exceeded worst case scenarios, and too much damage was being done to civilian infrastructure.

"What we saw from 23 September on is truly catastrophic," Riza said in an interview with Reuters on Thursday. He was referring to the day when Israel dramatically ramped up airstrikes in Lebanon, killing more than 500 people in a single day, according to Lebanese government figures.

"The level of trauma, the level of fear amongst the population, has been extreme," he said.

Israel says its campaign against the heavily armed, Iran-backed Hezbollah aims to secure the return home of Israelis evacuated from areas near the Lebanese border as a result of nearly a year of Hezbollah fire into northern Israel.

The Lebanese government says around 1.2 million people have been displaced by Israeli attacks on southern Lebanon, the Bekaa Valley, the southern suburbs of Beirut and other parts of the country. Some have been killed in Israeli strikes after having been displaced.

"You've got people being displaced from one place to another, thinking they were going to a safe place, and then that being struck," Riza said.

Riza said 97 medical and emergency workers had been killed - the majority of them in the last 10 days. There has been too much damage to civilian infrastructure, and civilians have been "bearing the great brunt of what's been going on", he said.

He noted that international humanitarian law requires that humanitarians be allowed to access people in need, and that civilian infrastructure and water systems be protected.

"This is what we call for when we're saying respect the rules of war in this," he said. "Unfortunately, we are seeing a situation where we have to go back to everybody and advocate for these basics in terms of protecting civilians."

An Israeli soldier was killed in combat in southern Lebanon on Wednesday, the Israeli military has said.

The latest warnings took the number of southern towns subject to evacuation calls to 70 and included the provincial capital Nabatieh, suggesting another Israeli military operation was imminent, further stoking fears of an all-out regional war.

Into Thursday, Israel bombed central Beirut in an attack the Lebanese health ministry said killed nine people. A Hezbollah-linked civil defence group said seven of its staff, including two medics, were killed in the Beirut attack. In response, Josep Borrell, the EU’s high representative for foreign affairs and security policy accused Israel of a possible breach of humanitarian lae: “Not only civilians are victims of attacks, including in densely populated areas, but they are deprived of emergency care. I condemn this violation of IHL [international humanitarian law],” he wrote on X, formerly Twitter. Israel denies all such accusations.

Chief International Correspondent Bel Trew and International Editor Chris Stevenson report:

Russian Deputy Foreign Minister Mikhail Bogdanov held a meeting with the Israeli envoy to Moscow Simona Halperin on Thursday, the Russian Foreign Ministry said.

The ministry said Bogdanov and Halperin discussed the situation in the Middle East, including Gaza and Lebanon, but provided no details.

The Islamic Resistance in Iraq has said it has attacked a target in southern Israel in a statement issued on Thursday.

The Israeli military has said it has intercepted a drone in southern Israel.

It added that no injuries have been reported.

US President Joe Biden has said “we are discussing that” when asked whether he would support Israel striking Iran’s oil facilities.

Reporters put the question to Biden as he left the White House on Thursday, with the US president appearing to hesitate at the end of his answer.

The BBC reports Biden’s words caused the price of crude oil to surge 5 per cent to $77 a barrel.

At least 28 on-duty medics have been killed in the past 24 hours in Lebanon, where Israel has launched airstrikes and sent troops to fight Hezbollah in an escalating conflict, the World Health Organization chief said on Thursday.

"Many (other) health workers are not reporting to duty and fled the areas where they work due to bombardments," Director-General Tedros Adhanom Ghebreyesus told an online press briefing, calling for stronger protections for health workers.

"This is severely limiting the provision of mass trauma management and continuity of health services," he said.

The global health agency will not be able to deliver a large planned shipment of trauma and medical supplies to the country on Friday due to flight restrictions, he added.

WHO's representative in Lebanon Dr Abdinasir Abubakar told the briefing that all of the healthcare workers killed in the past day had been on duty, helping with the wounded.

A total of nearly 2,000 people have been killed, including 127 children, and 9,384 injured since the start of Israeli attacks on Lebanon over the last year, the country's health ministry said.

"Hospitals have been already evacuated. I think what I can say for now is the capacity for mass casualty management exists, but it's just a matter of time until the system actually reaches its limit," said the WHO's Abubakar.