Fighting erupted on April 15, 2023 between the regular army, led by Abdel Fattah al-Burhan, and the paramilitary Rapid Support Forces, headed by his former deputy Mohamed Hamdan Daglo.

Khartoum quickly became a battleground. Bodies lined the streets. Hundreds of thousands fled. Those left behind struggled to survive.

"I've lost half my bodyweight," said 52-year-old Abdel Rafi Hussein, who stayed in the capital under RSF control until the army retook it last month.

"We're safe (now), but still, we suffer from a lack of water and electricity and most hospitals aren't working."

The army's recapture of Khartoum marked a turnaround after more than a year of setbacks.

Many civilians celebrated what they called the "liberation" from the RSF, whose fighters were accused of widespread looting and sexual violence.

But now the RSF is seeking to cement its grip on the vast western region of Darfur, where it has launched a deadly assault on El-Fasher -- the last major city in the region outside its control.

More than 400 people have been killed in the offensive which saw the paramilitaries overrun the nearby Zamzam displacement camp on Friday, the United Nations said.

An estimated 400,000 civilians fled the famine-hit camp as the RSF advanced, according to the International Organisation for Migration.

The army said on Tuesday that it had carried out "successful air strikes" against RSF positions northeast of the city.

In total, the conflict has displaced some 13 million people, 3.8 million of them abroad, according to UN figures.

- 'Catastrophic consequences' -

In London on Tuesday, international officials were meeting to "agree a pathway to end the suffering", British Foreign Secretary David Lammy said.

But neither of the warring parties was attending.

"Instability must not spread -- it drives migration from Sudan and the wider region, and a safe and stable Sudan is vital for our national security," Lammy said.

UN refugee chief Filippo Grandi said Sudan had faced "indifference from the outside world".

"The Sudanese are besieged on all sides -- war, widespread abuses, indignity, hunger and other hardships," he said, warning that "continuing to look away will have catastrophic consequences".

Precise death tolls are not available because of the collapse of the healthcare system, but former US envoy Tom Perriello cited estimates of up to 150,000 dead.

Both sides have been accused of targeting civilians, shelling homes and blocking aid.

Some 25 million people face acute food insecurity, and eight million are on the brink of famine.

For those returning home to army-recaptured territory, life is only marginally better.

Zainab Abdel Rahim, 38, returned to Khartoum North this month with her six children, only to find their home looted beyond recognition.

"We're trying to pull together the essentials, but there's no water, no electricity, no medicine," she said.

- Flow of weapons -

The United Nations says 2,776 children were killed or maimed in 2023 and 2024 -- up from 150 in 2022 -- and the real toll is likely higher.

The war has "shattered the lives of millions of children across Sudan," said Catherine Russell, executive director of UNICEF.

The Zamzam camp, which had been sheltering up to a million people before it fell to the RSF last week, was the first place in Sudan where famine was declared.

Other nearby camps have followed and famine is expected to be declared in El Fasher itself by next month.

On Monday, Guterres called for an end to "the external support and flow of weapons" fuelling the war.

"Those with greatest influence on the parties must use it to better the lives of people in Sudan -- not to perpetuate this disaster," he said, without naming any countries.

The army-backed government has accused the United Arab Emirates of arming the paramilitaries via neighbouring Chad, an accusation both Abu Dhabi and the RSF deny.

burs-bha/kir