Sydney  - A member of parliament for the ruling Labor Party on Friday called for Australia's immigration quotas to be cut in light of the threat from homegrown Islamic terrorists.

That threat was exemplified this week when five men were charged over an alleged plot to storm an army base in Sydney.

Kelvin Thomson said fewer migrants would mean more stringent background checks on applicants could be carried out.

He said Islamists were entering Australia through official immigration channels.

"That is a far more serious issue than the prospect of us being attacked by another country," he said.

Around 213,000 migrants arrived last year, of whom around 12,000 were refugees accepted through a United Nations programme.

Africa is now the biggest source of refugees, particularly troubled east-coast countries like Somalia.

Three of the five arrested and charged over the alleged plot to attack the army base were of Somali descent. The other two were ethnic Lebanese. All were Australian citizens. (dpa)