The UN Secretary-General has urged “utmost restraint” amid intensifying border clashes between Thailand and Cambodia as the Security Council met behind closed doors on Friday to address the most serious escalation between the two Southeast Asian neighbours in more than a decade.

The clashes, which began on 24 July, reportedly involved exchanges of gunfire, artillery shelling and rocket fire, with Thailand having conducted airstrikes inside Cambodian territory.

UN humanitarian officials confirmed civilian casualties, including children.

More than 131,000 people in Thailand and over 4,000 in Cambodia have been displaced, according to relief partners. Temporary shelters, including schools and temples, are overcrowded, and food, shelter and medical assistance are urgently needed.

The United Nations stands ready to support humanitarian efforts if requested, spokesperson Stephanie Tremblay said at a regular briefing in New York.

Protect children at all times

The UN Children’s Fund (UNICEF) also appealed for “maximum restraint”.

June Kunugi, Regional Director for East Asia and the Pacific – based in Bangkok – urged both countries to protect children and the critical services they depend on, in line with their obligations under international law, including the Convention on the Rights of the Child.

“Children must be protected at all times and their safety and wellbeing must be prioritised, while schools must remain safe spaces for learning,” she said.

Security Council private meeting

At UN Headquarters in New York, ambassadors convened for an emergency private meeting of the Security Council to discuss the situation.

Representatives of Thailand and Cambodia were said to be in attendance, with Khaled Khiari, Assistant Secretary-General for the Asia and the Pacific at the UN Department of Political Affairs (DPPA), briefing.

Private meetings of the Security Council are closed to the public, but considered a formal meeting.

A longstanding dispute

The last major flare-up between the two countries occurred in 2011, when days of border fighting near the historic Preah Vihear temple – a UNESCO World Heritage Site – left multiple casualties on both sides.

Then-Secretary-General Ban Ki-moon had called for an immediate, verifiable ceasefire and urged both countries to resolve their dispute through dialogue, not military means.

That escalation followed a 2008 troop build-up around the 11th-century Hindu temple, which sits on the Cambodian side of the border.