"The consequences are not confined to Sudan. They are destabilising the wider region," he told the gathering via a video message.
The conference host, German Foreign Minister Johann Wadephul, said that "largely beyond the public eye, the world's greatest man-made humanitarian catastrophe is unfolding in Sudan", adding that Germany would contribute 230 million euros in aid.
International donors pledged in total around 1.5 billion euros to tackle the crisis at the conference, according to a joint statement from several countries, as well as the African Union and EU, which organised the event.
As well as rallying donors, the conference aimed to help revive faltering peace talks, although the two sides fighting the war, the Sudanese army and the paramilitary Rapid Support Forces, have been excluded.
The vast majority of Sudanese people have been plunged into poverty by the conflict, which has spawned numerous war crimes allegations.
Mor than 13 million people have been forcibly displaced by the conflict, according to the organisers of the Berlin gathering.
"People are exhausted," said Amgad Ahmed, 42, in Omdurman, Khartoum's twin city. "Three years of war have worn people down. We have lost work, savings and any sense of stability."
Lethal drone strikes
The Berlin meeting brought together governments, aid agencies and civil society groups and followed similar conferences hosted by London and Paris over the past two years.
The war between Sudan's army and the RSF has killed tens of thousands of people.
Nearly 700 civilians have been killed in drone strikes since January alone, with attacks escalating on both sides, particularly in the southern Kordofan region and Blue Nile State, according to the United Nations.
A semblance of normality, however, has taken root in the capital since the army retook control of Khartoum last year.
In parts of the city, reconstruction has already begun. Markets have reopened, traffic has returned to streets that were once largely empty, while national secondary school exams were held this week after nearly two years of widespread school closures.
According to the UN, around 1.8 million people have returned to Khartoum.
But danger still lurks among the soot-stained buildings, with authorities slowly working to clear tens of thousands of unexploded bombs left behind by the fighting.
Al-Basheer Babker al-Basheer, 41, who visited Khartoum twice this year after three years away, said the city would need years to recover.
"I was happy to come back," he told AFP. "But when I went into the city centre, it was heartbreaking.
"The road to the university where I studied is no longer the same. The walls are black. They are not the same places we used to go to.
Stalled diplomacy
Diplomatic efforts towards peace led by the United States, Saudi Arabia, the United Arab Emirates and Egypt -- referred to collectively as the Quad -- have so far failed.
Saudi Arabia, Egypt and Turkey back the Sudanese army, while the UAE is accused of arming the RSF. All sides deny direct involvement.
Quad-led talks stalled after army chief Abdel Fattah al-Burhan accused the group in November of bias because of Abu Dhabi's membership.
UN rights chief Volker Turk told the Berlin meeting that he was "alarmed by the sharp increase in the use of drone warfare in recent months" in the conflict.
Drone strikes caused three-quarters of documented civilian deaths in the first three months of this year, he said.
The conference organisers, Germany, France, Britain, the United States, African Union and EU, said they were committed to ensuring Sudan "does not become a forgotten crisis".
"We urge all our partners to step up their efforts to bring the conflict to an end," their joint statement said.
