The ship carrying asylum seekers rescued from a sunken boat near the Cocos Islands has arrived at Christmas Island.

The LNG Pioneer recovered 27 survivors during the search and rescue operation earlier this week.

It's believed 39 people, including three children, were on board the boat when it sank on Sunday.

The 27 men who survived claim to be from Sri Lanka and are due to be off-loaded at Christmas Island later today.

Immigration Minister Chris Evans says the survivors will be offered counselling.

"They'll obviously be interviewed on arrival and receive the normal medical checks and then we'll interview them for identity and security purposes," he said.

"But we've also got in place trauma counselling because they've been through a pretty difficult experience and no doubt many of them will be affected by that."