Some of the world's poorest people are suffering as a result of the war on terror, a leading UK charity has said.
A child suffering from malnutrition
Christian Aid says the UK Government must halt a "dangerous drift" towards linking aid to fighting terror.
The report cites Iraq, Afghanistan and Uganda as places where funds have been "wrongly diverted".
The international development department said promises had been kept and funds earmarked for humanitarian aid had been spent as intended.
'With us or against us'
The report's lead author, John Davison, told BBC News Online: "Some of the world's poorest people are already paying for the war on terror as the giving of aid by the world's richest countries is ruled by the rhetoric of 'with us or against us'.
"This must not be allowed to continue.
"The blurring of the line between humanitarian and development activity and military and security activity by donors' governments is dangerous."
He said that in October 2003, the government diverted aid to fund reconstruction in Iraq - a three-year commitment totalling £544m - resulting in less money for "middle-income countries".
However, the term is a misnomer, Mr Davison said, as 140 million of the world's poorest people live in "middle-income countries".
Britain is unique in having legislation that states all aid must be targeted at poverty alleviation.
Christian Aid has not accused the government of acting illegally but wants it to try to halt and reverse the "dangerous international drift towards linking aid to the war on terror".
It said Afghanistan's $2.2bn in aid for 2004, for instance, is being diverted to military projects and emergency relief rather than long-term redevelopment.
The provision of humanitarian aid had become confused with the
security operation - leading to aid workers getting killed, it said.
In Uganda, the report says almost a quarter of the social services budget in 2002 was used to fund military operations for the government's civil war against the Lord's Resistance Army.
Hopes for a settlement in the 18-year war dealt
a severe blow by proscription of rebels as a terrorist organisation, according
to the report.
It perceived a drift "back to the days of the Cold War", when aid was used to serve the political and security needs of donor countries rather than the real needs of poor people.
Former Foreign Secretary Robin Cook called the report "compelling" and said it should be a "wake-up call" to the government.
"I find it particularly depressing that any of our aid effort should be diverted to fund the occupation of Iraq," he said.
"Regardless of what any of us may think about the invasion of Iraq, we surely can all agree that the poor around the world should not pay for the consequences."
A spokeswoman for the Department for International Development told BBC News Online the government had kept its promises on aid.
But she said that security and aid were inextricably linked in cases such as Afghanistan.
"Security is fundamental to achieve development," the spokeswoman said.
"We are there for the long term - we will continue to help to build a better country."