Defence Force chief Angus Campbell has expressed his willingness to return his Distinguished Service Cross.

Campbell was awarded the honour for his leadership during the Afghanistan conflict, which has been shown in a different light following the release of a damning report on war crimes committed by Australian soldiers. 

Reports say Campbell offered to return the medal to then-defence minister Linda Reynolds, who declined the offer due to Prime Minister Scott Morrison's objection to revoking any medals. 

Campbell and Reynolds have both refused to comment on the matter. 

The revocation of medals in light of war crimes allegations has become a contentious political issue, particularly after Victoria Cross recipient Ben Roberts-Smith lost his defamation case and was found to have unlawfully killed four unarmed civilians. 

The Brereton report, which uncovered credible evidence of 39 unlawful killings, recommended a review of commendations awarded during the conflict. 

Although most of the killings occurred after Campbell's command, the report held the officer corps partially responsible. 

Campbell, who has faced public scrutiny for questioning other officers about their medals, declined to disclose the number of letters he sent. 

Calls have been made for him to resign and surrender his medal by veterans groups and Senator Jacqui Lambie. 

Campbell is not the only senior officer willing to return his medal, as Brigadier Ian Langford also made a similar offer. 

The new Defence Minister, Richard Marles, is considering Campbell's recommendations on command accountability.