Army veteran Tyronne Gawthorne has apologised for failing to tell Australian team officials about his arrest in Cairns last month when he was allegedly found with drugs including cocaine and anabolic steroids.

The 36-year-old former rifleman denies taking any drugs that may have affected his performance at the Games Prince Harry founded for wounded and ill defence veterans.

"I met with team officials yesterday and agreed it is not appropriate for me to remain on the team and I will not compete in any more events," Gawthorne said in a statement on Wednesday.

"I cannot express how sorry I am for not disclosing to the team that I had been arrested.

"I have let down my family and friends and my team mates, and my actions are not in keeping with the spirit of the Games. I would like to sincerely apologise to everyone who has been affected by my actions."

Invictus Games officials released a statement Wednesday saying it was important people recognise the difficulties confronting both veterans and serving personnel.

"Our competitors are dealing with a complex range of challenges both physical and psychological," it said.

"Our primary concern is always the welfare of our competitors and we will work with all parties involved to ensure the appropriate support is in place."

After winning silver in middleweight powerlifting on Tuesday, Gawthorne was due to also compete in swimming and in the discus and shot put at the athletics.

Police charged Gawthorne, who served in Afghanistan and East Timor, with possessing dangerous drugs after he was allegedly found with cocaine, testosterone, and the anabolic steroids stanozolol and fluoxymesterone in the Cairns suburb of Mooroobool on September 17.

He was also charged with failing to safely secure a firearm in a vehicle and the unauthorised possession of restricted drugs including melanotan - commonly known as a "Barbie" drug used by people wanting a tan - and the breast cancer drugs letrozole and anastrozole.

Gawthorne, who suffers from PTSD, will face Cairns Magistrates Court on December 5.

He joined the army in 1999 and was deployed several times to East Timor and Afghanistan between 2009 and 2010 before being discharged a year later.

Gawthorne competed at last year's Invictus Games in Toronto, a few months after meeting Prince Harry when he visited Sydney to kick off the countdown to the Sydney Games.

The pair reunited briefly last Sunday when Harry spotted Gawthorne among the Invictus athletes and VIPs at a lunch hosted by Prime Minister Scott Morrison in Sydney's Domain and asked him if he had added any new tattoos since they last met.

Gawthorne obliged by lifting his shirt for the prince to show him a new tattoo on his back.

"He wanted to see if I had any new ones. I told him it is a traditional Samoan tattoo," Gawthorne told Fairfax.

Australian Associated Press