The price of oil soared over $145 today, fuelled by concerns of an attack on Iran by Israel or the US.

Investors are worried that continuing tension could push Iran to close the Strait of Hormuz - a route so strategically important that oil prices could rise even higher if traffic is blocked.

Where is Strait of Hormuz?

- The waterway separates Iran from the Arabian Peninsula and connects the Persian Gulf with the Gulf of Oman.

- The strait, which narrows to 34 miles across at the smallest point, is made up of 2-mile wide channels for tanker traffic and a 2-mile wide buffer zone.

Why is it so important?

- Nearly 40 per cent of the world’s traded oil supply passes through the Strait of Hormuz, travelling from countries like Iran and Saudi Arabia to the US, Western Europe and Asia.

- 90 per cent of oil exported from producers in the Gulf is carried through the passage.

- An estimated 13.4 million barrels of crude oil travel on tankers each day through the channel.

- The Energy Information Administration (EIA) predicts oil exports through the Strait will double by 2020 to between 30-34 million barrels per day.

- Two million additional barrels of oil products, such as liquid natural gas, are transported through the waterway daily.

- 31 million tonnes of exports per year from the world's largest liquid natural gas exporter, Qatar, are transported through the Strait to Asia and Europe.

- Other ships carrying perishable goods such as grain, iron ore and sugar, as well as finished goods travel through the Strait en route to major ports like Dubai and other Gulf countries.

Are there alternate routes?

- Alternate routes than the Strait would include the 745-mile-long Petroline across Saudi Arabia or the now deactivated Iraqi Pipeline.

Has Iran limited traffic in the strait before?

- In the late 1980s, Iran and Iraq engaged in a Tanker War where both countries fired on one another’s ships passing through the Strait, but some foreign-flagged vessels were caught amidst the crossfire.

Shipping dropped 25 per cent and the US helped to secure trade.

- In January 2008, Iranian speedboats sent a radio threat to blow up three US navy ships in the Strait, but sped away before any shots were fired. The White House warned Tehran to refrain from such provocative actions.

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