Diplomatic pressure has mounted to avert an escalation between Iran and Israel following high-profile killings that have sent regional tensions soaring.

United States President Joe Biden, whose country has sent extra warships and fighter jets to the region in support of Israel, held crisis talks on Monday with his national security team.

China's embassy in Beirut urged citizens to "travel with caution" should they visit Lebanon, warning they face "higher security risks" as fears of a regional conflict soar.

In a statement issued Monday evening Beijing time, the embassy warned citizens the situation in the country was "grave and complex".

Israeli warplanes raided Tuesday the southern village of Mayfadoun in the Nabatiyeh district, killing five Hezbollah fighters.

Another person was injured in a separate strike on al-Khiam and a child was wounded in artillery shelling on al-Wazzani.

Since last week, tensions have soared as Iran and Tehran-backed groups, including Hezbollah, vowed revenge for the killing of Hamas's political leader in Tehran and Israel's killing of the Lebanese group's military chief in Beirut.

Hezbollah has traded near-daily fire with Israel in support of its ally Hamas since the Palestinian militant group's October 7 attack on Israel triggered the Gaza war.

In Beirut, shops are open and traffic is as snarled as ever. In Tel Aviv, cafes hum with patrons and umbrellas sprout across crowded beaches.

Such scenes may seem surreal in a region teetering on the edge of all-out war — and beneath the surface there is plenty of fear and anxiety. But after 10 months of near-daily border skirmishes, strikes further afield and escalating threats, a sense of fatalism seems to have set in.

Diplomatic pressure mounted Monday to avoid an escalation between Iran and Israel following high-profile killings that have sent regional tensions soaring, while numerous governments urged their citizens to leave Lebanon.

Israeli Prime Minister Benjamin Netanyahu said late Sunday that his country was "determined to stand against" Iran and its allied armed groups "on all fronts".

French Foreign Minister Stéphane Séjourné will visit Beirut this week in an attempt by French President Emmanuel Macron to “prevent escalation in the region and continue to monitor the situation closely,” Annahar newspaper reported on Monday.

Macron had called King Abdullah II of Jordan on Sunday to disucss with him the explosive situations in the region.

U.S. Secretary of State Tony Blinken told his counterparts from the G7 countries on Sunday that an attack by Iran and Hezbollah against Israel could start as early as Monday, three sources briefed on the call told U.S. news portal Axios.

“Blinken convened the conference call to coordinate with close U.S. allies and try to generate last-minute diplomatic pressure on Iran and Hezbollah to minimize their retaliation as much as possible. He stressed that limiting the impact of their strikes is the best chance to prevent all-out war,” Axios said.

Israel's army said it had not changed "as of now" its policy for protecting civilians, as Iran and Hezbollah are expected to avenge killings blamed on Israel of two senior members.

"I would like to refer tonight to the various reports and rumors that we are on alert for the enemy's response to the territory of the State of Israel," military spokesman Rear Admiral Daniel Hagari said Sunday in an online briefing to journalists.

Travelers waited in long lines at Beirut airport on Sunday, some after cutting summer holidays short, as airlines have cancelled flights and fears have grown of all-out war between Israel and Hezbollah.

"I'm not happy to leave. I wanted to spend the whole summer in Lebanon then go back to work" in France, said Joelle Sfeir from the crowded departures hall at Beirut airport.