British Prime Minister Keir Starmer supports calls for FIFA to investigate Argentina players who displayed a banner asserting the country’s claim to the Falkland Islands after their World Cup semi-final victory over England, his office said.

After Argentina’s 2-1 win in the match in Atlanta, some players held up a banner which read: “Las Malvinas son Argentinas” using Argentina’s term for the South Atlantic islands.

Starmer endorsed a call by Business Secretary Peter Kyle for FIFA to “thoroughly” investigate whether displaying the banner breached rules banning political messaging or slogans on the field of play.

Asked about the incident, the prime minister’s spokesperson said: “The World Cup might not be ours, but the Falklands definitely are. Our position is unchanged, and our commitment to the Falklanders is unwavering.”

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The spokesperson confirmed Starmer supported Kyle’s call for FIFA to investigate the matter, adding that any subsequent action would be a matter for the governing body.

Asked who the prime minister would be supporting in Sunday’s World Cup final, the spokesperson said: “The PM wishes both teams well for the final – especially Spain.”

The islands in the South Atlantic are known to the British as the Falklands, and the Argentinians as the Malvinas.

Argentina claims it inherited the islands from Spain after its independence in 1816 and that Britain took control in 1833 through an illegal colonial act.

They also fought a short conflict over the islands in 1982.

FIFA’s Stadium Code of Conduct bans banners, flags, flyers, apparel and other paraphernalia that are of a political or offensive nature inside stadiums.