LONDON - National flags should not be "messed with", British Prime Minister Rishi Sunak said on Friday, after Nike's decision to use an altered design of the St George's Cross on England's soccer shirts angered some fans.

Nike, which makes the kit for England's national soccer teams, unveiled its new design this week, which it said paid homage to the country's 1966 World Cup-winning men's team.

It features the St. George's Cross, which is red on a white background and is England's national flag, but in shades of red, blue and purple on the back of the shirt collar.

Nike called the change a "playful update" that was meant to "unite and inspire", adding that the design "disrupts history with a modern take on a classic".

But the move has spurred calls from some fans writing on social media and calling in to radio shows to scrap the new design.

With a national election expected in Britain this year, in which cultural issues are likely to feature prominently, politicians from across the spectrum have commented on the design.

"Well, obviously, I prefer the original," Sunak told reporters. "My general view is that when it comes to our national flags, we shouldn't mess with them, because they're a source of pride, identity, who we are, and they're perfect as they are."

Opposition Labour Party leader Keir Starmer told The Sun newspaper that Nike should reconsider the design.

Nike said it understood "the significance and importance" of the St George’s Cross.

"It was never our intention to offend, given what it means to England fans," the U.S. sportswear giant said in a statement on Friday.

"The trim on the cuffs takes its cues from the training gear worn by England’s 1966 heroes, with a gradient of blues and reds topped with purple. The same colours also feature an interpretation of the flag on the back of the collar."

England's Football Association said it was not the first time that "different coloured St George's cross-inspired designs" have appeared on England shirts.

"We are very proud of the red and white St George’s cross – the England flag. We understand what it means to our fans, and how it unites and inspires, and it will be displayed prominently at Wembley tomorrow – as it always is – when England play Brazil," the FA said in a statement.

England play Brazil at Wembley in a friendly on Saturday, before hosting Belgium on Tuesday.

(Reporting by Sachin Ravikumar; Additional reporting by Simon Jennings Editing by Toby Davis)