Fairfax Media understands General Campbell will replace Lieutenant-General David Morrison, who is set to step down next month.

General Campbell, a former SAS commander and deputy army chief, became a public figure as the co-ordinator of the Abbott government's tough but ultimately successful policy of stopping asylum-seeker arrivals by boat.

Widely respected within the military, General Campbell brought a military approach to border protection, including rigid operational secrecy and strict co-ordination of different arms of government.

But he also became the subject of controversy over the boats policy, in particular his and then Immigration Minister Scott Morrison's consistent refusal to provide information about the operations that were being used to intercept and turn back boats, repeatedly citing them as "on-water matters".

He also used surprise tactics such as purchasing dozens of unsinkable, bright orange lifeboats that were used to send asylum-seekers back to Indonesia - which thwarted people-smugglers' previous tactic of scuttling their rickety fishing boats when the Australian Navy approached.

Ultimately, Operation Sovereign Borders, as the government's policy was called, was successful, bringing to a complete halt the arrival of asylum-seekers by sea.

General Morrison is set to step down in March. He became internationally known after delivering a steely speech on YouTube in which he told sexist soldiers to "get out" of the army, in the wake of the so-called Jedi Council affair.

General Campbell will take over the army at a critical juncture, with a new Defence White Paper and Force Structure Review due around the middle of the year, and the army embarking on a major procurement program to get about 800 new armoured combat vehicles.

General Campbell served in East Timor and commanded Australian forces in the Middle East, including Afghanistan. He was seconded for several years from 2005 to serve as a civilian national security adviser to the federal government.

Follow us on Twitter