The flotilla making its way from Australia towards Papua is expected to cross Indonesia's marine border today.

Organisers of the "Freedom Flotilla" say they aim to let the world know about human rights abuses in the country's disputed Papua region.

The group of around 20 people embarked on their journey last month. The crew includes Aboriginal elders, West Papuan refugees, filmmakers and other activists. On Monday the group left Horn Island in the Torres Strait.

Australia's Department of Foreign Affairs and Trade has warned the group that they will not receive any extra consular assistance if they are arrested or detained by Indonesian police.

Organiser Lizzy Brown spoke to Radio Australia's Pacific Beat from on board the flotilla's flagship vessel.

"Today we've been really contemplating the whole auspicious occasion of being September 11 and the whole thing of anti-terrorism," she said. "And that I guess Australia's been training Indonesian troops like Detachment 88 to wreak havoc and terror on West Papuan people."

Responding to suggestions by the Indonesian Navy that the yacht may potentially be armed, Ms Brown said they "come in peace, bearing no arms."

"We have been absolutely clear about this from the beginning of our journey at the sacred mound springs of Lake Eyre in Arabunna country," she said in a statement. "We are letting them know our location via our satellite tracker which is available for the world to see up on our website."

Deputy chief of Papuan police Paulus Waterpauw says unauthorised boat arrivals will be intercepted by the navy and probably detained by immigration authorities.