UNICEF warned on Tuesday that further escalation between Israel and Hezbollah would be "catastrophic" for all children in Lebanon, urging an immediate de-escalation.

"On Monday alone, at least 35 children were reportedly killed in Lebanon. This is more than the number of children killed in Lebanon in the past 11 months. Eleven months in one day. 35 children, in one day among 492 reportedly killed," UNICEF deputy representative to Lebanon Ettie Higgins told a U.N. press briefing in Geneva on Israeli airstrikes.

Noting that over 1,645 people were also injured during those airstrikes, Higgins stressed that "more children are in danger as I speak, exposed to ongoing attacks, displaced from their homes and unable to rely on an overstretched and under-sourced health system."

"If we return to a conflict, like those dark days of 2006, I fear this time could be even worse for the children of Lebanon," she said.

She underlined that families in Lebanon are already "at the brink" due to economic and political crisis.

"Any further escalation in this conflict would be catastrophic for all children in Lebanon, but especially families from villages and towns in the south and the Bekaa, in Eastern Lebanon, who have been forced to leave their homes," the UNICEF official said.

She noted that these newly displaced add to the 112,000 people who have been displaced since October.

UNICEF urgently calls for an immediate de-escalation and for all parties to uphold their obligations under international humanitarian law to ensure the protection of civilian infrastructure and civilians, including children, humanitarian workers and medical personnel, Higgins said.

She added that it includes facilitating the safe movement of civilians seeking safety.

"Yesterday was Lebanon’s worst day in 18 years," she said. "This violence has to stop immediately, or the consequences will be unconscionable."