Sir Keir Starmer is relying on a proposed state visit by King Charles III to the White House on July 4 as a key diplomatic lever to manage tensions with US President Donald Trump over tariffs and Greenland. The visit, marking the 250th anniversary of the US Declaration of Independence, has taken on huge significance as Trump imposes new tariffs and renews threats against allies.
According to sources, the royal family is one of the few cards the UK holds in its dealings with Trump, who reveres Britain’s royals partly due to his late mother’s Scottish heritage. Prince William has already been deployed as a go-between, speaking regularly with Trump since late 2024, even more than Starmer does.
The prospect of a second state visit to the UK helped Starmer secure a trade deal and ensured Trump did not reject Lord Mandelson as ambassador. Trump fixated on the visit, telling those close to him he did not want anything to interfere with it, making him more amenable to the UK.
However, if the UK enters recession due to tariffs or Nato collapses over Greenland, a senior royal visit would seem impossible. The threat of cancellation might stay Trump’s hand, but cancelling risks a personal slight that could worsen relations. Starmer faces a difficult tightrope walk in the diplomatic turbulence of the Trump presidency.
