(Corrects identity of Australian company impacted by cyber attack in paragraph 5)
By Colin Packham
SYDNEY, Sept 1 (Reuters) - Australia will embed intelligence officers in some private companies, the head of the country's chief cyber intelligence agency said on Tuesday, as Canberra seeks to strengthen its defences after a spate of attacks on critical infrastructure.
Citing estimates that cyber attacks on businesses and households are costing about A$29 billion ($21.5 billion) or 1.5% of the country's Gross Domestic Product, Australia said last month it would spend A$1.66 billion over the next 10 years to strengthen companies' cyber defences.
"We already started to partner with a number of companies and actually agreeing to embed each other's staff, so that we better understand what we have in terms of a threat picture," Rachel Noble, head of the head of Australian Signals Directorate (ASD) - the country's cyber intelligence agency - said in a rare public speech in Canberra.
Noble did not name the companies, but described them as "crucial private sector companies".
Australia's drive to strengthen cyber defences comes amid a spate of cyber attacks this year, whose targets have included Bluescope Steel BSL.AX and Lion Co -- the Kirin 2503.T -owned Australian brewer.
The corporate attacks follow Australia's most high-profile cyber-attack, a 2019 hack of Australia's parliament and three largest political parties.
Reuters reported late last year that Australia determined China was responsible for the attack, though Beijing denies it. = 1.3512 Australian dollars)