Ranko Berich, head of market analysis at Monex Europe, said: "The dollar saw wild swings along with other macro markets last night after Donald Trump’s unexpectedly strong performance in key swing states, notably Florida.
"Markets were happily assuming that a clear Biden and Democrat win would lead to large stimulus spending, a higher path for inflation, and a weaker dollar. This narrative was blown to pieces by early results from Florida.”
Nigel Green of deVere Group said: “This monumental uncertainty in the world’s biggest economy is going to send global stock markets into a tailspin as investors get rattled about a clear outcome taking longer to reach than they hoped.
He added: “A chaotic contested outcome is exactly what the markets did not want.
“The markets had priced-in a Biden victory and ultimately they may still be right – but it’s going to get messy first.”
Neil Wilson, chief market analyst at Markets.com: "Donald Trump just declared war by declaring victory in the election before all the counting is over.
"He’s played the voter fraud card and this has undoubtedly unsettled markets as a long and protracted battle in the courts is precisely what investors do not want.”
The unease in the City was palpable.
Many traders and analysts had worked through the night, advising clients and rapidly adjusting positions. Asked which sectors would benefit from the coming chaos, one trader said “lawyers” and hung up.
