The London Stock Exchange’s leading FTSE 100 index plunged more than 200 points, or 2.7%, within moments of opening in reaction to Russia’s invasion of Ukraine.

On Thursday Vladimir Putin confirmed action on Ukraine, stating in a televised address that Russia does not have a goal to occupy Ukraine, but said the responsibility for bloodshed lies with the Ukrainian “regime”.

This has caused The London Stock Exchange’s leading FTSE 100 index to drop significantly.

Brent crude oil has also reached highs of $102.48 on Thursday, rising by more than five per cent, reports the Independent.

Last week, Foreign Secretary Liz Truss warned Russian's invasion of Ukraine would come at a high economic cost.

She told BBC Breakfast: “First of all, if we did see a war in Ukraine, that would have a very damaging impact on oil and gas prices across Europe. This is why we need to reduce dependence on Russian gas, find alternative sources."

She added: “In fact, in the United Kingdom only 3% of our gas is from Russia, which is different from continental Europe.

“What we’ve done in the UK is we’ve frozen petrol duty for a number of years, saving people £15 on their filling-up of petrol. And we’re working to support families with the cost of living but, of course, a war in Ukraine would do further damage to the European gas market.”

READ MORE: Russia invades Ukraine: Read Vladimir Putin statement in full

Mr Putin also warned other countries that attempt to interfere with the Russian action would lead to “consequences they have never seen”.

This comes as the UK’s ambassador in Ukraine, Melinda Simmons, repeated a call for Britons to leave the country.

Aircrafts flying to or from UK airports are now being ordered to avoid Ukraine airspace after the crisis intensified on Thursday.

Transport Secretary Grant Shapps said he made the decision “following the horrific events overnight” as Russia launched a major military assault.

The Cabinet minister tweeted: “I’ve instructed @UK_CAA (the Civil Aviation Authority) to ensure airlines avoid Ukraine airspace to keep passengers and crew safe.