Dairy Crest has fired another salvo in its battle to promote British butter.

The company has taken out full page newspapers advertisements in its bid to boost sales of its Country Life brand.

Advertisements featuring former Sex Pistols front man John Lydon appeared in The Times and the London-based Metro on Tuesday (19 May).

They come days after New Zealand farmers asked Mr Lydon – better known as Johnny Rotten – to travel down under and see how their butter is made.

The Country Life advert asks readers: “Do you know where your butter comes from?”

Some 39% of people who buy Anchor butter think it is British when actually it comes from New Zealand, says the advert.

“We’ve nothing against New Zealand, it’s a fantastic place,” it continues.

“But if you prefer to buy British and support British farmers then Country Life is the natural choice.”

Sales of Country Life butter have boomed since Mr Lydon started promoting it in a series of TV commercials.

The ageing punk rocker is credited with increasing sales by more than 80% – although some of his fans have accused him of selling out.

The advertising campaign has angered New Zealand farmers who claim their Anchor butter brand is better.