The government has said it is relocating people so the area can be developed
The UK and US have ignored human rights abuses carried out by Ethiopia's government as it forcibly evicts tens of thousands of people from their land, a US think tank has said.
The relocations are taking place in the Omo Valley to make way for commercial farming and a big dam, the Oakland Institute says in its report.
The valley is a World Heritage site.
The UK government denied that aid money was being used to force people from their homes.
"Our assistance has helped millions of people in Ethiopia, a country that has suffered famine and instability over many decades," said a spokesman for its Department for International Development (DfID).
The Ethiopian government has said it has been relocating people so it can develop the area and provide better services.
The BBC has contacted the Ethiopian government for comment about the Oakland Institute report, but has received no response as yet.
'Political coercion'
In response to earlier allegations about human rights abuses, DfID and USAid had launched a joint investigation in January last year, which found the accusations were "unsubstantiated", the Oakland Institute said.
The think tank said the investigation had turned a blind eye to testimony that was collected by its researchers. They were accompanied by the author of the Oakland Institute report Will Hurd, who recorded and translated the interviews.
The final aid report ignored interviews showing that soldiers had raped people from the cattle-herding Bodi and Mursi ethnic groups who opposed their relocation, the Oakland Institute said.
"[The soldiers] went all over the place and they took the wives of the Bodi and raped them, raped them, raped them. Then they came and raped our wives," a Mursi man is quoted as telling the DfID and USAid investigators.
The Oakland Institute said the "violent" resettlement programme, which affects some 260,000 people, had UK and US aid "fingerprints all over them".
"Information around forced evictions, beatings, killings, rapes, imprisonment, intimidation and political coercion has been shared and these tactics have been documented as tools used in the resettlement process," it said.
"It is worrisome that aid agencies rubber stamp development projects that are violating human rights. Worse, they have chosen to ignore the results of their own investigations," it added.
"It is worrisome that aid agencies rubber stamp development projects that are violating human rights. Worse, they have chosen to ignore the results of their own investigations," it added.
The UK and US are major donors of Ethiopia, a key ally in the campaign against militant Islamist groups in the region."It is worrisome that aid agencies rubber stamp development projects that are violating human rights. Worse, they have chosen to ignore the results of their own investigations," it added.
It receives an average $3.5bn (£2.3bn) a year in development aid, equivalent to 50% to 60% of Ethiopia's budget, the Oakland Institute said.
"We condemn all human rights abuses and, where we have evidence, we raise our concerns at the very highest level," DfID's statement to the BBC said.
"To suggest that agencies like DFID should never work on the ground with people whose governments have been accused of human rights abuses would be to deal those people a double blow," it said.
Ethiopia's government plans to create sugar plantations in the area which will be irrigated in part by the Gibe III hydropower project.
The dam, which would become Africa's largest and the fourth-biggest in the world, has provoked much controversy.
The Ethiopian government says that the project must be completed in order to bring energy and development to the country. But campaigners fear it will fuel conflict over already scarce water resources, and rob communities of their livelihoods.
The valley is one of the most ecologically and culturally diverse areas on the planet and is currently home to eight different agro-pastoral communities, they say.
Many other African countries are reserving huge tracts of land for commercial agriculture - often leased by foreigners in order to export the crops cultivated there.http://www.bbc.co.uk/news/world-africa-23344154
