A French peacekeeper has been killed and three others wounded after a UN patrol came under fire in southern Lebanon, in what officials described as a deliberate attack.

The soldier was serving with the United Nations Interim Force in Lebanon (Unifil), which confirmed that one peacekeeper had died and three others were injured, two of them seriously, when their patrol came under small-arms fire.

French President Emmanuel Macron blamed the attack on Hezbollah. The Iran-backed armed group denied any connection to the incident.

It comes amid heightened tensions in southern Lebanon, where peacekeepers have faced growing risks since renewed fighting between Hezbollah and Israel erupted on 2 March.

A 10-day ceasefire between Israel and Lebanon came into effect on 16 April. The US, which announced the deal, urged Hezbollah to abide by its terms.

Everything suggests that responsibility for this attack lies with Hezbollah, Macron said.

France demands that the Lebanese authorities immediately arrest the perpetrators and take their responsibilities alongside Unifil.

France's Armed Forces Minister Catherine Vautrin said the peacekeeper had been part of a mission to reopen access to a Unifil position that had been cut off by the recent fighting when it had been ambushed by an armed group at very close range.

Vautrin added that he was hit immediately by a direct shot from a small arms weapon and was pulled away by fellow soldiers, who were unable to revive him.

Unifil said the patrol had been clearing explosive ordnance along a road in the village of Ghanduriyah to reconnect isolated positions.

It said the team came under fire from what it described as non-state actors and condemned the attack as deliberate.

The Lebanese Armed Forces said the incident followed exchanges of fire with armed individuals, while coordinating closely with Unifil during what it described as a sensitive phase in southern Lebanon.

Lebanon's President Joseph Aoun condemned the attack and told Macron during a phone call that those responsible would be brought to justice.

Prime Minister Nawaf Salam has also ordered an investigation.

Hezbollah issued a statement denying responsibility, calling the accusations rushed and baseless, while urging caution regarding the incident pending further investigations by the Lebanese army.

In March, three Indonesian peacekeepers were killed in separate incidents involving explosive devices in the region. Unifil stressed that deliberate attacks on peacekeepers could amount to war crimes.

This incident marks another tragic event for peacekeeping forces in Lebanon, where over 330 peacekeepers have lost their lives since the mission started in 1978.