The vast wealth generated by oil fields, power plants, extortion, taxes, and the pillaging of antiquities has rendered ISIS the most well-funded terrorist group in history, experts have warned.

With an estimated £1.3billion fortune, the group can afford not only to pay foreign fighters who join its cause in the Middle East, but easily expand beyond its borders to launch attacks in the West.

A new report illustrating the massive expansion ISIS has undertaken in the past year offers chilling detail showing exactly how the organisation is funded.

The terrorist group ISIS, led by Abu Bakr al-Baghdadi (pictured), has become the wealthiest terror group in history through a combination of robbery and extortion, and imposing taxes on its territory much a like a state

A new report reveals the group has become the deadliest group operating in the world today and is responsible for more than 6,000 deaths through terror attacks and 20,000 battlefield deaths last year alone

This includes £1million per day in crude oil sales, kidnappings worth £30million per annum, income taxes of 20 per cent across a population of 10 million, and control of 40 per cent of Iraq's wheat production.

This wealth has allowed the group to flourish regionally and internationally, and presents a unique challenge for world leaders attempting to suppress the bloodthirsty jihadis.

Just days after multiple ISIS terror cells massacred at least 129 people, Steve Killelea, Executive Chairman of the Institute for Economics and Peace, told MailOnline: 'We're seeing a change in tactics out of ISIS in the Middle East that's epitomized by the attacks in Paris at the weekend.

'They're developing tactics to extend. There's also a tendency by ISIS and Boko Haram to target more civilians and that's a shift away from military people and government targets.

'I think what they're finding is that it creates greater mayhem, they can get more casualties, and it's a softer target and we can certainly also see the effect it's had on Paris over the weekend in creating panic among the general population.'

THE TOP 10 COUNTRIES FACING GREATEST THREAT OF TERRORISM 1. Iraq 2. Afghanistan 3. Nigeria 4. Pakistan 5. Syria 6. India 7. Yemen 8. Somalia 9. Libya 10. Thailand Advertisement

He added ISIS is now essentially functioning throughout Syria and Iraq as a state using taxes, with a black market economy and mafia-style extortion tactics.

'I think what we're looking at is a well funded terrorist organisation - the funding gives it the ability to be able to pay for soldiers and fund terror acts beyond its borders.'

His comments come on the eve of the release of his organisation's Annual Terrorism Index, which reveals ISIS and Nigeria-based Islamic militants Boko Haram are the world's two deadliest terror groups.

Discounting the estimated 20,000 deaths it inflicted on battlefields throughout the Middle East, ISIS last year also caused 6,073 deaths in 1,071 terror attacks, making it by far the most destructive group operating in the world today.

An expert contribution to the report, provided by Christina Schori Liang from the Geneva Centre for Security Policy, offered compelling detail on exactly how ISIS is funding its wholesale slaughter.

She described the 10 oilfields through Iraq and Syria controlled by the militants as its 'black gold'.

'Oil wealth serves several purposes: it provides energy needs for the estimated 10 million civilians living in [ISIS] controlled territory and it helps fuel the war machine.

'More importantly, oil is used as a leveraging device to control its enemies. Many opposition forces are dependent on [ISIS] for diesel.'

Incredibly, ISIS earns an estimated £1million every day selling 34,000 - 40,000 barrels of crude oil at the well head to independent traders.

This crude oil is then smuggled through the region by a black market network of traders and is consumed in Turkey, Iran and Jordan.

It also controls at least eight power plants in Syria. Remarkably, gas supplies 90 per cent of the power grid used in both ISIS and regime-controlled territory.

An ISIS fighter parades through the Iraqi town of Baiji in a plundered Iraqi military vehicle after the militants seized the city's oil refinery in an offensive in June 2014

Illustrated here is the top 10 deadliest terror attacks to take place across the world last year. In first, second and fourth places are atrocities carried out by ISIS. Nigeria-based Islamic militants Boko Haram featured in third, seventh, eighth and ninth spots

While the two forces battle for control of these resources, neither side is prepared to destroy such a valuable asset.

She added: 'In territories now under [ISIS] control, there is a 10 per cent income tax, 10-15 per cent tax on business revenues, and a 2 per cent value added tax on everyday purchases.

'There are road taxes and custom taxes for vehicles crossing [ISIS] held territory and taxes for smuggling drugs and weapons.'

The terrorists also require citizens to pay a 'departure tax' of £650 for anyone wishing to leave their territory.

'Fearing that many will leave, [ISIS] requires that civilians sign over car titles and family homes in order to just to leave its territory for two weeks,' she added. 'Christians are forced to pay jiza, a religious levy or "protection tax," unless they convert to Islam.'

It has also generated vast funds by pillaging two state-owned banks in Mosul - and an astonishing 90 privately owned banks.

A member of the French special forces evacuates people from near the Bataclan theatre on Friday night following the shootings in Paris which ISIS has claimed responsibility for

A woman is evacuated from the scene of the massacre, where witnesses said gunmen threatened to kill anyone who moved. Experts say ISIS's vast wealth is facilitating its spread beyond the Middle East

Another graphic illustrates deaths from terrorism have increased dramatically since the Syrian Civil War began

This table, documenting the increase in terror attacks in recent years, represents a nine-fold increase from 2000 to 2014

Other rackets include control over the production of wheat and the looting of historical antiquities, while extortion stemming from kidnappings netted them £30million last year alone.

Countering claims the group may soon face expenses it cannot cover, Dr Liang warned this did not account for the fact it operates as a 'mafia state', akin to North Korea, which can conduct its business internally even if ostracized.

'[ISIS] is not as vulnerable as other terrorist groups because they can exploit their own tax base by holding territory they can tax and raise revenue at will.

'To emphasise its transparency and professionalism, it publishes an annual report which sets out its business strategy of terror and destruction, including specific investments, down to the cost of each suicide mission.'

Meanwhile, the Global Terrorism Index also revealed so-called 'lone wolf' attacks, carried out by individuals inspired but not necessarily taking orders from terrorist groups, are the single biggest threat to the West.

These are responsible for 70 per cent of attacks in the West since 2006.

Globally, terrorist activity increased by 80 per cent from the previous year. This marks a ninefold increase from 2000.

The majority of this increase stemmed from the growth in attacks throughout Africa and the Middle East.