Gaza is experiencing a health catastrophe that will last for generations to come, the director-general of the World Health Organization (WHO) has warned.

Dr. Tedros Adhanom Ghebreyesus told BBC Radio 4's Today programme that a massive increase in aid is needed to begin to address the complex needs of the Strip's population.

Israel has allowed more medical supplies and other aid to cross into Gaza since a ceasefire with Hamas came into effect on 10 October, but Dr. Tedros said levels are below those needed to rebuild the territory's healthcare system.

His intervention comes as the US attempts to shore up the ceasefire it helped to broker following an outbreak of violence at the weekend.

The agreement has been described by the White House as the first phase of a 20-point peace plan that includes an increase to the amount of aid entering Gaza, and supplies distributed without interference from either side.

Dr. Tedros welcomed the ceasefire deal but noted that the increase in aid that followed has been smaller than expected.

Gazans have faced famine, overwhelming injuries, a collapsed healthcare system, and disease outbreaks fueled by the destruction of water and sanitation infrastructure.

Dr. Tedros highlighted the fatal combination of these issues as catastrophic and beyond words and emphasized that the crisis will impact generations to come.

He stated, If you take the famine and combine it with a mental health problem which we see is rampant, then the situation is a crisis for generations to come.

Tom Fletcher, head of the United Nations Office for the Coordination of Humanitarian Affairs, noted that while aid groups are addressing the starvation crisis, much more support is necessary.

On Tuesday, the UN's World Food Programme reported that more than 6,700 tonnes of food had entered Gaza since 10 October, though well below the 2,000-tonne daily target. Dr. Tedros emphasized that 600 aid lorries a day need to arrive, but currently, the average is between 200 and 300.

Israel recently halted aid deliveries after Israeli troops were attacked but resumed following international pressure. Dr. Tedros urged that aid should not be weaponised and called for unconditional access to aid, particularly after the release of hostages by Hamas.

He also pointed out that thousands of Palestinians await medical evacuation flights, with recent delays contributing to loss of life. Dr. Tedros reiterated that peace is essential for recovery, stressing that the ceasefire remains fragile with ongoing violence.

The UN estimates a total reconstruction cost of $70bn for Gaza, with about 10% earmarked for restoring its health system. He remarked, We have been saying for a long time that peace is the best medicine.