British ministers are under growing pressure to use the UK's substantial aid budget in Rwanda as a lever to end the civil rights abuses that are tarnishing the reputation of a country seen until recently as one of Africa's greatest success stories.
David Cameron is one of a succession of British leaders who have pinned their hopes for Africa on President Paul Kagame. But a series of incidents in which opponents of the government have been threatened or killed and free speech suppressed has raised embarrassing questions about the wisdom of the huge political and financial investment that the UK has made in Mr Kagame's regime. He is credited with bringing stability to the country after the horrors of the 1994 genocide. After 16 years in office, he is likely to be announced landslide winner today of a presidential election in which his only opponents were junior politicians accused of being ruling party stooges.
British aid to Rwanda is currently "under review", but officials privately admit that they are in a quandary, reluctant to penalise the poor – in a country where more than half the population lives on less than 25p a day – for alleged abuses by their rulers.
Rwanda's government is recognised as generally free of financial corruption. The country featured prominently in Mr Cameron's campaign to change the image of the Conservative Party when in opposition. Conservative Party volunteers have gone to Rwanda every summer as part of its social aid programme.
Andrew Mitchell, the International Development Secretary, is a regular visitor, returning to the UK on Sunday after helping out at a school in Kigali. Tony Blair, another Kagame cheerleader, visited Rwanda in June as patron of a charity that promotes good governance in Africa.
Last year, the Labour government committed the UK to providing £46m a year in aid to Rwanda, making Britain the biggest international donor to the Kagame government, almost half of whose budget comes from foreign aid. But that aid came with conditions that committed Rwanda to "poverty reduction and sound financial management; good governance and respect for human rights".
Tom Porteous, London director of Human Rights Watch, warned that everything that the UK has invested in Rwanda in 16 years could be put at risk if repression causes a build up of resentment that could trigger another conflict.
"The government should give more thought to using its leverage to restore proper respect for human rights in Rwanda itself instead of just burying its head over this problem," he said.
"We've had meetings with the Foreign Office and the International Development department, and with Andrew Mitchell. We don't see eye to eye with them but I think we are beginning to get through."
Aid agencies also believe the Government should be leaning on Mr Kagame to clean up his act. An Oxfam spokesperson said: "In recent years, British aid has helped Rwanda make great strides in tackling poverty. UK aid can also play a vital role in strengthening Rwandan civil society organisations so that they can hold their government to account and promote human rights."
Rwanda's Foreign Minister, Louise Mushikiwabo, has confirmed that British officials have raised their concerns. She said: "The UK Government wants to know what is going on and wants to be reassured that they will not happen again." But she also said she expected British aid to continue, and to be "upscaled".
A spokesman for the Department for International Development said: "Andrew Mitchell has met the High Commission in Rwanda, NGOs and Human Rights Watch to discuss aid and other matters, including these crimes that we have been hearing about. It's something he is taking a close personal interest in. We have got this review of bilateral aid, and we will report later in the year. Human rights will play a part."
Rwanda's President has enjoyed similarly close relations with Washington, despite warnings from critics such as Robert Kruger, former US Ambassador to neighbouring Burundi. Writing in Foreign Policy magazine this week, Mr Kruger said: "Over the past decade and a half, Kagame has masterfully exploited the benefit of the doubt he receives from the international community to consolidate his power. The nation he leads with Western assistance has become more efficient and neatly run than other Central African countries... But we must not suppose that it is a free society. "