Mahmood Hassan is indignant about the challenge from foreign office minister Denis MacShane to Britain's Muslim community, asking its members to make it clear where their loyalties lie after the bomb outrages in Istanbul. "It was not something very pleasing to hear from a minister," says the chairman of Islamic Aid. "The Muslim community and its leaders have been very robust in condemning terrorism, but that gets no attention.
"It's only when some minority group or even a single individual says something different that there's a lot of noise in the media. It's perfectly possible to be a good Muslim and a good British citizen. We don't ask Christian and other religious groups to prove their loyalty all the time, do we?"
The MacShane spat was another example of how the climate of suspicion since 11 September has made life more difficult for Britain's Muslim communities, not least because government agencies and potential critics have been on the look-out for the diversion of funds from Islamic charities to terrorist groups.
But that climate seems to have done little harm to the ongoing expansion of Islamic Aid, the charity which Hassan launched in Britain four years ago to fund humanitarian and development work, mainly in Pakistan, Afghanistan and Palestine. Its income grew to £1.3m last year, and Hassan is confident that he can persuade more of Britain's 2 million Muslims to contribute.
At present there are 21,000 donors, 2,000 of them giving regularly via standing order.
"After 11 September, you have to be very careful, especially when you're sending support to other organisations," says Hassan. "You can find out what an organisation is doing, but you don't always know everything it's doing. One safeguard is to use volunteers - it's a matter of finding people who do things on a small scale.
"We try to be as neutral as possible, but if something is causing suffering you have to highlight it. You may have your own views, but from the point of view of Islamic Aid the focus is need. Our campaigning and lobbying is just raising awareness of the humanitarian situation."
One example of the charity's work is funding a school for girls in northern Pakistan, which is run by a former naval officer who wanted to do something useful in his retirement. "We have supported him wholeheartedly," says Hassan.
But he hasn't managed to avoid political controversy entirely. At an Islamic Aid fundraising event for Palestinian medical work earlier this year, the Prime Minister's wife Cherie Blair made a remark which was seized on by the Daily Mail and other national newspapers. Talking about the situation in the Middle East, she said: "As long as young people feel they have got no hope but to blow themselves up, you are not going to make progress." The remark is reproduced without comment on Islamic Aid's website, in a section called "influencing."
Hassan declines to talk about it. "We'd better not go into that area," he says. But in Palestine, he explains, Islamic Aid is interested in identifying a cluster of projects for long-term development around Hebron, with requests for help coming from the municipality and local schools.
Islamic Aid is run from a two-room office costing £100 a week in a nondescript building in Walthamstow in north-east London. It's not very grand, but until the beginning of November it had been run from Hassan's home nearby.
He's hired four part-time staff for the peak donation period of Ramadan, which ended last week, but there are no full-time workers. The bulk of the work is done by volunteers and by Hassan himself, who is critical of small charities that hire strings of people.
"Some our size have five or six staff - a CEO, director of finance and so on," he says. "They spend £50,000 doing not much more than producing accounts, and we get the same things done for about £1,200."
So how has such a slimline organisation built up such a substantial income so quickly? "That's my secret," smiles Hassan. "Over the years, I have learned the tricks of raising funds and expanding a donor base. It's to do with skill and an understanding of ethnic minorities and the Muslim community."
Hassan first came to Britain from the Punjab in 1988 when he won a Pakistan government scholarship to study for an MBA at Imperial College, London.
His first voluntary sector job was head of fundraising for Islamic Relief during the war in Bosnia. But the charity was based in Birmingham and, in order to move back to London, Hassan joined Muslim Aid, the charity then supported by Yusuf Islam, the former pop star Cat Stevens.
He was head of fundraising and chief executive, and during his time there the number of donors increased from 5,000 to 44,000 and the income from £1.5m to £3.5m.
He then spent more time on his business career, and started Islamic Aid as a part-time activity which took off in 2000. His speciality is using direct mail to elicit donations from a database of about 850,000 UK Muslims.
He says his basic approach remains the same: "It's obviously important to help refugees and the victims of disaster, war and conflict, but we point out that behind the headlines the suffering of people goes on because of poverty and hunger. More people die from those than from all the disasters.
It is the conflict headlines which move people, but behind them lies a background involving food, education and employment. We try to communicate to our potential supporters how important these things are."