The agency was handed the business for the cider brand after a five-way pitch, overseen by creativebrief. The intermediary is also handling a review to find a UK ad agency to create the campaign for the roll-out.
Strongbow introduced its Gold branding in February 2007, to target the overseas market. It was initially launched only in France, Germany and Spain.
The brewer plans to use the established UK brand to fill an apparent gap in international markets, where cider consumption is not as heavy.
It is understood that the brand's name will vary by territory. Local marketers may use either the name Strongbow Gold or Strongbow.
Bulletproof has been briefed to devise bespoke packaging for the drink for each market.
Brewer Scottish & Newcastle was acquired by Heineken last year, and Strongbow will look to take advantage of Heineken's wider distribution network to launch the brand in Asia and North and South America, as well as support its relaunch in Europe.
In the UK, Scottish & Newcastle has previously worked with packaging design consultancy Jones Knowles Ritchie.
In 2005 the agency was tasked with overhauling the Strongbow brand to capitalise on a resurgence in cider sales.
The brand's UK ad account is handled by St Luke's. In August the agency launched a campaign to reposition it as a drink for working-class men.