The leader of a group of extremist Muslims who planned a "foreign incursion" to help overthrow the government of the southern Philippines in 2016 has been sentenced to seven years in prison.

Key points: Robert Cerantonio is the last of the group of six to be sentenced over the overthrow plot

Robert Cerantonio is the last of the group of six to be sentenced over the overthrow plot Justice Michael Croucher said Cerantonio had a higher degree of culpability as the leader of the group

Justice Michael Croucher said Cerantonio had a higher degree of culpability as the leader of the group The court previously heard the men spoke in code, adopted aliases and sought bank loans to fund their trip

Robert Cerantonio, 34, is the last of six Melbourne men who have now been convicted of preparing to go to the troubled region of Mindanao "with the intent to engage in hostile activity".

The men purchased a boat and a four wheel drive vehicle to tow it to Cape York.

They also bought survival gear as well as navigational equipment, and had drawn maps of the seas near their targeted destination.

They were intercepted before they could sail to the Philippines in what Justice Michael Croucher said was a trip "foredoomed to failure".

The men were planning to sail to the southern Philippines in a "foreign incursion." ( ABC News )

"It's hard to imagine they would have made it very far past the breakers," Justice Croucher said.

Justice Croucher said Cerantonio, along with Paul Dacre, Antonino Granata, Shayden Thorne, Kadir Kaya and Murat Kaya, "agreed to encourage acts … directed [to] … overthrow by force or violence the government of the southern Philippines" between October 2015 and May 2016.

Each of the men "had an affinity with Islamic extremism", particularly Cerantanio, who has been described as the group's "leader and religious adviser".

Justice Croucher said Cerantonio had a higher degree of culpability as the leader of the group and because he was the one who convinced the others to take part in the plot.

He referred to Cerantonio's "misguided and dangerous religious thinking" and his history of encouraging others to support or engage in religious violence.

Cerantonio must serve at least 5 years and three months in jail before he is eligible for parole.

A court sketch of six Australians charged with planning to sail to the Philippines to encourage Muslim militants to stage a government overthrow. May 17, 2017. ( ABC News )

He had spent a year living in the Philippines before he was deported in 2014 and had publicly preached support for Islamic State in Iraq and Syria and advocated for sharia law.

Cerantonio was brought up as a Christian and had converted to Islam at the age of 17.

During a plea hearing in March, his lawyers told Justice Croucher Cerantonio was not a typical Islamic extremist — while he preached and posted extreme material to social media sites, his views were "somewhat nuanced", his lawyers had argued.

Defence barrister Jarrod Williams said this was evidenced by the fact Cerantonio had an "eclectic" mix of music on his phone when he was arrested, which included artists such as ACDC, Bob Marley, Edith Piaf, Cold Chisel and Queen.

Group had no experience with boats

In earlier hearings, Justice Croucher heard the men spoke in code, adopted aliases and sought bank loans to fund their trip. None of them had any experience with boats.

The court was told the group was originally planning to sail with their wives and children but could not find a suitable boat.

In February, Dacre, Granata and Kadir Kaya were each sentenced to four years in prison, with a non-parole period of three years.

Murat Kaya was sentenced in February over the plot. ( AAP: Tracey Nearmy )

Murat Kaya was sentenced to a jail sentence of three years and eight months, with a non-parole period of two years and nine months.

Shayden Thorne, 31, was given a jail term of three years and ten months, with a non-parole period of two years and ten and a half months.

With time served, Thorne was able to apply for parole in March but the Federal Attorney-General has since declined to release him.