As its friends and benefactors criticise Rwanda and its actions in the neighbouring Democratic Republic of Congo, the clamour will, rightly, grow for Britain to get tough as well. The news that first the US and then the Netherlands had suspended aid to President Paul Kagame, the donors' darling, marks a reluctant acceptance by some in the international community that Rwanda must be held accountable for what it does outside as well as inside its borders.

Those who are waiting for Britain to go much further than it has done in delaying a modest disbursement of cash have likely misunderstood London's relationship with Rwanda. Its critics have pointed out the shortcomings of President Kagame's small Central African state: the absence of real democracy, the jailing of some opponents and the state-sponsored assassination of others. But these issues have rarely threatened UK relations with Rwanda. Britain is spending more proportionally on foreign assistance to Rwanda than any of its allies and has long ago taken the view that what it needs in Africa are examples where aid works.

That is exactly what Mr Kagame has offered. The remarkable aid spend on the country, as it has recovered from the 1994 genocide, was capped earlier this year when it achieved the development wonk's hat-trick of rapid growth, sharp poverty reduction and reduced inequality.

That is why donors are inclined to turn a blind eye to the government's reported support for rebels across the border in eastern Congo. The same rule applies to Ethiopia where Western donors have silently decided that they need an example of how their aid works more than they need another democracy. The difference is that Addis Ababa embraces its role as regional policeman, hosting US drone bases.

The Coalition is almost as close to Mr Kagame as is Tony Blair – who still holds a post as a government adviser – and many Conservatives would have to change their summer holiday plans if visiting gorillas and aid projects in Rwanda was suddenly taken off the table.

But it can no longer pretend that UK money sent to help Rwanda is helping the cause of peace in Central Africa.