The plan, a revised version of the annual humanitarian plan for 2023, is designed to target 18 million people in need.
Meanwhile, the UN refugee agency is also seeking more funding to assist those forced to flee.
"Today, 25 million people, more than half the population of Sudan, need humanitarian aid and protection.
"This is the highest number we have ever seen in the country," said Ramesh Rajasingham, head of the UN Office for the Coordination of Humanitarian Affairs in Geneva and director of the Coordination Division
"The funding requirements of nearly $2.6 billion dollars are also the highest for any humanitarian appeal for Sudan."
The plan, a revised version of the annual humanitarian plan for 2023, is designed to target 18 million people in need.
The conflict between the Sudanese army and the paramilitary Rapid Support Forces (RSF) has caused a humanitarian crisis that threatens to destabilise the region, displacing more than 700,000 people inside Sudan and forcing about 200,000 to flee into neighbouring countries.
The United Nations High Commissioner for Refugees (UNHCR), making a joint appeal with the aid agency on Wednesday, said it was seeking $472 million to assist more than one million people over the next six months.
"Sadly, we once again need to call on countries and individuals with the means to step up for innocent people who have lost everything through no fault of their own," said Raouf Mazou, Assistant High Commissioner for Operations at UNHCR.
Eyewitness? Submit your stories now via social or:
Email: eyewitness@pulse.ng