unilateral
n. An independent journalist, particularly a war correspondent who is not officially sanctioned by the military.
Examples
2003
The Anglo-American coalition, along with its Kuwaiti allies, have never been keen on the "unilaterals," as they call the independent journalists. All privileges were given instead to the carefully selected group of official "embedded" journalists who travel with U.S. or British military units.

But the military's hostility to the unilaterals has steadily worsened in recent days. In some cases, coalition soldiers have detained journalists and escorted them forcibly out of Iraq. In other cases, British troops have refused to allow unilaterals to camp near their checkpoints or in facilities such as ports that they control.
—Geoffrey York, “What it's like to be an independent journalist,” The Globe and Mail, April 01, 2003
1990 (earliest)
The normally feisty press has hardly ruffled a feather in protest. Worse, as former network correspondent Marvin Kalb wrote last week in the New York Times, there is "a certain whiff of jingoism on the airwaves and in print." Nor did the situation improve when the Pentagon pool was supplanted by the 300 or so "unilaterals" — nonpoolers — who have been admitted to Saudi Arabia since the crisis began. For one thing, the rules and limits on access that applied to the pool have largely remained in effect for all journalists. Reporters had neither the freedom nor logistical means — nor, it sometimes seemed, the Vietnam-era gumption — to scour the potential battlefronts in search of stories.
—Stanley, “The First Casualty,” Time Magazine, September 10, 1990