A former Special Armed Services member and friend of Ben Roberts-Smith has been accused of resisting arrest and pushing an Australian Federal Police officer.

The man, who can only be identified as Person X, gave evidence in Mr Roberts-Smith's defamation trial and was taken into custody yesterday.

9News understands he was back at his hotel when AFP officers arrived with a warrant to seize his phone. It's alleged he resisted those orders and pushed one of the officers.

The former SAS soldier is now facing two charges, including causing harm to a Commonwealth official.

He was released on a $10,000 bond and is now free to return home overseas as long as he returns to Australia for any hearing of the case.