The British government can send people from Darfur back to Sudan if their claims for asylum have failed, despite fears for their welfare, the country's highest court ruled yesterday.

The House of Lords overruled the Court of Appeal, which decided in April that it would be "unduly harsh" to send three Darfuri asylum seekers to Sudanese refugee camps because of the oppressive conditions there.

The government appealed against the ruling, trying to reinstate the original decision of an immigration tribunal that the three men - identified only by their initials - could be sent back to Sudan.

The test case could affect up to 1,000 Darfuris who have sought shelter in Britain from violence and human rights violations in western Sudan.

International experts estimate 200,000 people have died in the Darfur conflict and 2.5 million have been driven from their homes in four-and-a-half years of fighting between rebel groups and government forces and militias.

The three men in the case say they would be persecuted if returned to Darfur. The British government said they could be safely returned despite harsh conditions in refugee camps.

The House of Lords said the Court of Appeal should not have questioned the immigration tribunal's findings.

Aegis Trust, a group that campaigns to prevent genocide, urged the government to halt any further deportations to Sudan. The trust said two asylum seekers previously sent back had said they were tortured by Sudan's security services when they arrived in Khartoum.

"We are obviously disappointed if this results in any Darfuris being returned," Aegis campaigns director Stephen Twigg said.

The Court of Appeal made no ruling in April on whether or not Darfuris might face torture if returned to Sudan.

Britain's Home Office (interior ministry) said in a statement: "We will continue to uphold Britain's proud tradition of providing humanitarian protection. We agree with today's decision by the House of Lords that people facing persecution in Darfur can safely and reasonably relocate to Khartoum.

"We will do everything we can do to help those who do not need our protection to go home voluntarily," it said.