Are we heading for World War Three? Experts give their verdicts

"It depends on your definition of World War Three. A possible conflict between Iran and Israel has the potential to expand into a major military conflagration in the Middle East, with global implications."The US would almost certainly be drawn in on Israel's side and other Western countries, including the UK, may do the same to a lesser extent.

"But their involvement would be limited and this would not be World War Three, not least as Russia can ill-afford to support Iran and because China is unlikely to.

"The impact of such a conflict on Europe would be primarily economic, through further disruption in energy flows and trade.

"The primary pathway to a World War Three scenario remains a direct Western clash with Russia. That scenario will be more likely if Donald Trump wins and undermines NATO, tempting Vladimir Putin into an attack on the Baltics.

"A clash with Russia would also be quite likely if Western forces become involved in supporting Ukraine in frontline combat roles," said Luigi Scazzieri, senior research fellow at the Centre for European Reform think-tank.