Home Office plans to send Darfuri asylum seekers back to Sudan have been blocked by senior judges.
Displaced: Thousands of Darfuris are in need of supplies
The Court of Appeal in London said the three asylum seekers could not be sent to Sudan's capital Khartoum.
The three appeal judges said oppressive conditions in refugee camps would be "unduly harsh" on the individuals.
Darfur has seen conflict between black and Arab Sudanese people. The Home Office said the men would be safe in Khartoum and will challenge the ruling.
Some two million people in Sudan are living in camps after four years of fighting.
The UK immigration service had planned to put the three men, who are black, on a plane to Sudan.
It had planned to place them in a refugee camp near to the capital Khartoum - on the other side of the country from Darfur. The removal was approved at an earlier hearing before asylum adjudicators.
In their challenge, the three men, identified only as AH, IG and NM, said they risked torture at the hands of the Sudanese government.
They also said they would be deported to extremely poor conditions in squatter or refugee camps on the edge of the capital.
The three had been subsistence farmers before fleeing, saying they had faced persecution from the Arab Janjaweed militia.
In their judgement, Lord Justice Buxton, with Lords Justices Moore-Bick and Moses, blocked the deportations because of oppressive conditions in the refugee camps and a lack of resources for economic survival.
This total alteration in the life of a refugee meant that resettlement would be "unduly harsh".
Many camps had been demolished, leaving 250,000 people homeless with no water or other services on the edge of a desert, they said.
While rejecting claims that the men would face torture, the judges said the home secretary would not live up to international obligations by sending Darfuris to the proposed camps.
Conditions in the camps made "frightening reading", said Lord Justice Buxton.
While the number of Darfuri asylum seekers in the UK is believed to be small, with 675 applications last year, the judgement may mean a block on any returns in current circumstances.
Similar battles have been fought over other nationalities, including the return of Zimbabweans.
A spokesman for the Home Office's Border and Immigration Agency said it believed non-Arab Darfuris could live safely in Khartoum and it would consider seeking permission to appeal to the House of Lords.
The Janjaweed are accused of ethnic cleansing
"We are disappointed that the Court of Appeal has over-ruled the Asylum and Immigration Tribunal's decision that allowed this.
"The court did not find that non-Arab Darfuris would be at risk of mistreatment in Khartoum.
"Instead it found that they would be ill-equipped for city living, and that conditions could be worse for them than those in Darfur."
Anna Reisenberger of the UK's Refugee Council said it was "scarcely believable" that the Home Office wanted to return people to Sudan.
She said the Home Office's policy contradicted the US government's view that the Sudanese government was complicit in genocide.
"There have been countless reports recently of the deteriorating situation in Darfur," she said.
"The government should now be concentrating its efforts in this area on preventing the situation getting any worse, and supporting the countries who are shouldering by far the biggest responsibility for protecting these people."