The press campaign, created by DLKW Lowe, is also promoting its Morrisons Miles Card, which offers 10 'Morrisons Miles' for every litre of petrol bought.
Customers who collect 5,000 points can redeem them for a £5 Morrisons shopping voucher.
The deal will run from today (23 February) until Sunday 11 March, and is being pushed under 'The great fuel Britannia' strapline".
Morrisons' latest fuel war is even more aggressive than the one it launched last year, which offered 6p off a litre when customers spent £40 in store.
The supermarket launched that deal last April in order to trump its rivals, after Sainsbury's began offering 5p off for those who spent £50 or more in-store and the Co-op offered a 5p discount to shoppers who spent £30.
Last year's 'Fuel Britannia' campaign was launched to play on the national pride generated by the Royal Wedding.
Follow Matthew Chapman at @mattchapmanUK