Prime Minister Malcolm Turnbull's linking of the European refugee crisis with the Brussels bombings is dangerous, the Belgian ambassador says.
Mr Turnbull warned in a speech on Wednesday that Europe faces a "perfect storm" from failed or neglected migrant integration, foreign fighters returning from Iraq and Syria, and porous borders.
He said recent intelligence showed the Islamic State group was using the refugee crisis to send its operatives into Europe.
But Belgium's ambassador to Australia Jean-Luc Bodson said such comments were dangerous.
"It's dangerous because it's precisely what (Islamic State) wants - that we would make a confusion between terrorism and migrants and between terrorism and Islam," Mr Bodson told the ABC on Thursday.
"My view is that the terrorists who committed the latest attacks in Paris and in Belgium are European-raised and born. Maybe from foreign origins, but they are Europeans.
"So it has nothing to do with the refugee crisis and I think that is the main danger to assimilate that."
Mr Turnbull told the ABC's Lateline program on Thursday the Australian government carefully checks refugees.
"ASIO and our other agencies, the AFP and so forth, are taking great care in ensuring that those people who come in are as far as we can ascertain not people that would pose any security risk to Australians and we make no apology for that," he said.
Opposition Leader Bill Shorten said it was a "bit early" to start diagnosing what had happened in Brussels.
Australia's national terror threat level is unchanged at "probable" following Tuesday's airport and metro attacks in Brussels that killed at least 31 people and injured more than 200.
Australians are being advised to reconsider any travel to Belgium.
Security has been stepped up at Australia's international airports.
European security officials said one of the suicide bombers was Najim Laachraoui, a Moroccan-born Belgian whom police had been hunting as the suspected bombmaker in the November 13 attacks in Paris that killed 130 people.
The other two suicide bombers were Belgian-born brothers, Ibrahim and Khalid El Bakraoui, both known to the police as common criminals, not anti-Western radicals.
An unidentified fourth man shown in airport video surveillance footage remains at large after his suitcase bomb failed to detonate properly.
