The Prime Minister Malcolm Turnbull has extended his condolences to victims of the terror attack in London.
"The attack on the British parliament is an attack on parliaments, freedom and democracy everywhere," he told reporters on Thursday morning.
"We will never, ever let the terrorists win. We will defeat and destroy them on the battlefield, we will defeat and defy them at home.
"We will never change the way we live. We will never let them divide us."
WATCH: PM Turnbull condemns London attack
Mr Turnbull said he is yet to speak to the British Prime Minister Theresa May as she continues to deal with the fallout from the deadly attack.
But he did confirm Australia's terror threat level remains at 'probable'.
"The Australian Federal Police commissioner has confirmed there will be an increase in police present in Parliament House here in Canberra today," he said.
"We are very alert to the vulnerabilities of places of mass gathering and the risk of lone attackers, like the perpetrators, the terrorist in London."
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The Chinese Premier Li Keqiang and his wife Cheng Hong arrived in Canberra last night for a five day visit to Australia.
The Premier will be ceremonially welcomed to Parliament House this morning, followed by meetings with the Mr Turnbull, the governor-general and the opposition leader.
Watch: Julie Bishop responds to the London attack