Sri Lanka's navy says it has detained 152 people who were attempting to migrate illegally to Australia in fishing trawlers.

It says naval ships detained 69 people on a trawler off Sri Lanka's west coast on Tuesday and 83 others on two other boats off its east coast on Monday.

It says all 152 were Sri Lankans and were handed over to police.

It is illegal in Sri Lanka to leave from unauthorized ports. The maximum sentence is five years in prison.

Police say so far this year they have arrested about 1,200 Australia-bound Sri Lankans, Indians, Pakistanis and Afghans.

Last week, Australia's Parliament passed tough new legislation aimed at deterring a flood of asylum seekers making perilous sea journeys to the country's shores.