The drive is an attempt to combat the launch of the Sainsbury's-backed Nectar super-loyalty scheme and Tesco's long-standing ClubCard.
The mailing, to Sainsbury's and Tesco shoppers living in the catchment area of Safeway stores, offers shoppers 拢10 off petrol when they spend 拢50 on four separate occasions at the store.
Each pack will include a unique reply number, which will be used for post-campaign data analysis.
Gavin Hilton, 141 planning director, said: "The major supermarkets have concentrated their efforts on loyalty cards, but loyalty is a fragile thing and it doesn't take much to change behaviour patterns. Our consumer insight research suggests that four shopping trips would be enough to switch a shopper to Safeway, particularly when they see the new-look stores."
The promotion, which is an additional offer to Safeway's existing Petrol Payback scheme, is also being pushed by leaflets handed out by staff at stores.
It was devised by 141 creative team Neil Woodley and Roland Haftenrichter.
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