The Ftse 100 has dropped this morning in reaction to the US attacking three Iranian nuclear sites and Iran's subsequent threats to close the Strait of Hormuz trading route.

London's stock exchange opened 25 points lower once trading began, with Asian markets also falling dramatically as tensions between the US and Iran reach fever point.

Japan’s Nikkei was 60 points, or 0.15 per cent after dropping around 200 points in early trading. Ahead of the Ftse's opening, European futures pointed to markets on the continent open lower.

US stock markets are also expected to open lower in response to President Donald Trump's decision to green light airstrikes on the Islamic Republic's key nuclear sites.

The Ftse 100 slipped this morning in reaction to global conflict

Following the sites being targeted, the Iranian Parliament voted to close the Strait of Hormuz, a vital trade route for the global economy, which is expected to impact oil prices.

Around a fifth of the world’s oil supply, 20m barrels, and much of its liquified gas, passes each day through the trading route.

US Vice President JD Vance claimed Iran's potential closure of the Strait of Hormuz would have serious consequences for Tehran itself, as well as the wider economy.

He explained: "Their economic system is dependent on this waterway. There is no reason for them to see such a step."

Donald Trump gives 'last chance' to Iran to make a deal as Britain tells US President that bombing Tehran puts Westerners at riskREUTERS/GETTY