A boat carrying asylum seekers has reached Australia's remote Cocos Islands territory.

The last documented asylum seeker boat arrival to Australia was in 2014.

The number of asylum seekers arriving by sea plunged after the government introduced tough new policies, including the towing back of boats.

Australia also sends all intercepted asylum seekers to offshore locations such as Manus Island in Papua New Guinea and Nauru.

The boat arrived within the Cocos Islands on Monday morning.

It came within 500m of Home Island before it was intercepted by Australian authorities.

Australia's immigration department would not comment on the incident.

The Cocos Islands are a remote chain of islands and atolls located between Sri Lanka and the west coast of the Australian mainland.

Australia's government says the journey asylum seekers make is dangerous and controlled by criminal gangs, and they have a duty to stop it.

However, critics say opposition to asylum is racially motivated and is damaging Australia's reputation.

Two asylum seekers on Nauru have set themselves on fire in the past fortnight, including a 23-year-old Iranian man who died of his injuries.

Australia and asylum

The number of asylum seekers travelling to Australia by boat rose sharply in 2012 and early 2013. Scores of people have died making the journey.

To stop the influx, the government adopted tough measures intended as a deterrent.

Everyone who arrives is detained. Under the policy, asylum seekers are processed offshore at centres on Nauru and Manus Island in Papua New Guinea.

The government has also adopted a policy of tow-backs, or turning boats around.