European stocks sink after Trump tests positive for Covid-19

The region's main bourses later clawed back some losses but were still languishing in negative territory, while many investors flocked to the safety of haven currencies.

At about 0720 GMT, London's benchmark FTSE 100 index dropped 0.7 percent to 5,839.95 points, Frankfurt's DAX 30 lost 0.9 percent to 12,620.75 points and the Paris CAC 40 shed 0.8 percent to 4,783.28.

The extraordinary setback for Trump, 74, has immediate political consequences just 31 days before election day, forcing him to cancel campaign trips and adding new volatility to a contest already steeped in tension.

"The increase in political uncertainty connected with Trump's diagnosis is ... weighing on stocks and stock futures, and supporting safe havens such as the yen, Swiss franc and the US dollar," Rabobank analyst Jane Foley told AFP. 

"The extent to which the election campaign is affected will depend on the outcome for Trump's health -- but there are sufficient unknowns at this stage to fan speculation that the election could be quite different from the one that was expected just 24 hours ago."

The White House doctor has said that both were well and that Trump would continue his presidential "duties without disruption".