The banking crisis was avoidable, says Islamic scholar Sheikh Hussain Hussan
London has become one of the biggest centres for Islamic finance in the world, with five Islamic banks, and many others in the high street offering Islamic financial products, or "windows" as they are known.
The growth of Islamic finance has been an unexpected outcome of the attacks on the World Trade Center of 11 September 2001.
Islamic finance is based on rules from Islam's holy texts - the Koran. Scholars claim the fundamental difference to conventional banking is that Islamic finance is more ethical.
First it bans any form of "riba" or interest, preventing consumers being exploited by high rates of borrowing.
Secondly, it regards speculative trading as sinful. One of the world's leading experts on Islamic finance, Sheikh Hussain Hassan, argues the whole crisis in Western banking could have been avoided if these basic sharia principles had been followed.
He said: "$600 trillion were wasted on options, futures and derivatives, all gambling. Sharia prohibited these kind of risks 14 centuries back."
We have a policy of no obstacles, no special favours, towards Islamic banking or indeed any new financial company
Financial Services Authority
Some Muslims regard ordinary mortgages as sinful. The idea is for the lender and the borrower to share the risk. There are now more products on the market which help Muslims buy a house without paying interest.
The most common form of Islamic home purchase loan works like this: When a couple wants to buy a house, instead of borrowing the money, the Islamic bank buys 80% of the house for them.
The couple puts down a deposit for the other 20% and then pays the bank rent, plus regular portions of the capital. During the fixed period, ownership gradually passes from the bank to the buyer. The rent charged by the bank is how it makes its money.
If the borrower loses his job and defaults on the payments, under sharia law it is very difficult for the family to be thrown out of their home, as that would be seen as a creditor exploiting a debtor.
These interest-avoiding transactions can work on a bigger scale as well.
Farmida Bi explains why London is now attracting Muslim investment
The old Chelsea Barracks in London was bought by the Qatari government for nearly £1bn - the biggest residential property deal in the UK.
The entire transaction was done under sharia pinciples, with contracts drawn up by lawyers at Norton Rose.
Farmida Bi, one of the law firm's partners, explained that London has attracted this kind of investment because the British government wooed Islamic money in the wake of 9/11, at the expense of the US.
"It was really September 11th that made being a Muslim a political statement and not just a matter of personal faith," she said.
"And with the Patriot Act, which made investments in the US difficult for many Islamic investors, there was a significant increase in Islamic investors choosing to invest in Islamic institutions and Islamic products."
So while groups in the US were investigating terrorist connections with Islamic banks, Muslim investors pulled their money out of America.
Some of the money got diverted to London, which had traditionally been a banking centre. The British government then helped further by changing regulations to give sharia-compliant funds a level playing field with conventional ones.
Salaam Insurance offers Europe's first sharia-compliant car insurance
A spokesperson for the Financial Services Authority, the body which regulates UK financial services, said: "We have a policy of no obstacles and no special favours towards Islamic banking, or indeed any new financial company."
The desire of British Muslim consumers to affirm their identity is also leading to a growth in new consumer services.
Salaam Insurance has launched Europe's first sharia-compliant car insurance aimed at Britain's 700,000 Muslim drivers.
Bradley Brandon-Cross, its non-Muslim chief executive, finds most Muslims do not yet understand the profit and loss sharing principles of "takaful" that it is based on.
"There's clearly an education campaign we are undertaking for British Muslims, to help them understand what Islamic finance is and what it means for them," he said.
Critics say the Islamic character of the products is merely window dressing to lure in Muslim customers.
And others argue the scholars who authorise them are a narrow group whom financial institutions choose to support their new services.
But this scepticism is unlikely to halt the inexorable growth of Islamic finance - as big investors and growing numbers of Muslim consumers demand it.
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