Boatload picked up near Christmas Island (1)

CANBERRA - A boatload of 85 Sri Lankans are being housed on board a naval ship after being intercepted heading to Christmas Island.

Border protection officials have been monitoring the leaky boat since it was first spotted by a plane on Monday.

Immigration Minister Kevin Andrews said the group agreed to come on board HMAS Success last night, and would remain there temporarily.

Mr Andrews said the vessel was not engaged in any legitimate commercial activity and the men were "potential unauthorised arrivals".

His office late today said the men had indicated their intention to reach Christmas Island but had "not expressed any particular intent" towards claiming asylum.

HMAS Success intercepted the boat in international waters, about 50 nautical miles from Christmas Island, early Tuesday.

"During subsequent contact between HMAS Success and those on the boat, it was determined that their vessel was unseaworthy," Mr Andrews said in a statement.

"Because of fears for their safety if they remained on the unseaworthy vessel, the group agreed to come aboard HMAS Success last night."

"This group will remain on board HMAS Success until more details are available."

Mr Andrews' office could not say where the men would be taken next.

"Once all the initials are done, all their health and wellbeing checks, then obviously some decision will be made about forward steps," a spokeswoman said.

The men appeared to be in good health, his office said.

Refugee advocates today said it was likely the men will be taken to a detention centre on Christmas Island or to Nauru for processing under the so-called "Pacific Solution".

But they called on the government to bring the men to Australia for processing if they attempt to claim asylum.

WA-based Project SafeCom spokesman Jack Smith expressed concerns that while the men remained on the ship their treatment could not be scrutinised.

David Manne from the Refugee and Immigration Legal Centre said the immigration minister had discretion to intervene and allow the men to apply for protection in Australia.

"What is essential is they get independent assistance to help them explain their case," he said.

Greens immigration spokeswoman senator Kerrie Nettle agreed the men should be given legal support so they understood their rights.

"If they are (asylum seekers), the Greens believe they should be brought to the mainland so they can be processed while they live in the community," she said.

"We don't want them on Christmas Island where it's more expensive to keep them and they don't get the same level of support and legal assistance, and we certainly don't want them take to Nauru."