An open beta for upcoming PlayStation Vita shooter Killzone Mercenary will go live to North American PlayStation Plus subscribers next Tuesday, August 20, and to European subscribers the following day on August 21, Guerrilla has announced.

The beta will remain exclusive to PlayStation Plus subscribers for one week, before opening to non-PS Plus subscribers on August 27 in North America and August 28 in Europe. It'll close on September 3.

The beta gives Vita owners the chance to experience Mercenary's multiplayer mode over two weeks before the game launches on September 6, which Guerrilla describes as "the most advanced, addictive multiplayer experience on the Vita".

"The team at Guerrilla Cambridge put in a lot of blood, sweat and tears to make Mercenary's multiplayer package the most advanced experience to-date on the PlayStation Vita," said the developer. "We're very excited for launch, but we think the Open Beta will definitely hold you over until September!"

Killzone Mercenary is already shaping up to be one of the most visually-impressive titles on the handheld, which Steve said reminded him of "just how powerful Sony's handheld is" after going hands-on with the game last month.