The Australian sharemarket slumped to its worst weekly performance since April after a late Friday sell-off sparked by US President Donald Trump's shock COVID-19 diagnosis.

The news rattled global markets, driving the S&P/ASX200 Index down 81.4 points, or 1.4 per cent, to 5791.5 points on Friday and pushing the benchmark to a 2.9 per cent loss for the week - the worst performance since the week ended April 24.

Banks and miners accounted for the bulk of the losses. BHP fell 3.2 per cent, Westpac tumbled 2 per cent and Telstra lost 1.1 per cent.

Gold stocks gained as the precious metal jumped from $US1890 an ounce before the news to $US1907 an ounce late on Friday.

Evolution Mining rose 0.9 per cent, Newcrest Mining gained 0.8 per cent, St Barbara rose 1 per cent, and Saracen added 1 per cent.

Energy stocks were hit hard as Brent crude fell from $US40.60 a barrel before the news to $US39.40 a barrel late on Friday. Woodside fell 4.3 per cent and Santos slumped 5.5 per cent.

Tech stocks enjoyed solid gains on Friday. Xero gained 0.8 per cent and EML Payments added 3 per cent.

Mesoblast's plunged 37 per cent as the FDA ordered the company to conduct another clinical trial to support the efficacy of its remestemcel-L drug in treating pediatric patients with severe acute-Graft Versus Host Disease (aGVHD).

Janus Henderson jumped 9.4 per cent on reports US activist investor Trian had taken a 9.9 per cent stake in the funds management group.

US media reported Trian Fund Management, which was co-founded by Nelson Peltz, has also taken a 9.9 per cent stake in Invesco.