Prince William donned a green puffer jacket by Canadian sportswear brand, Lululemon, suggesting subtle signs of support for the country. It comes as the Canadian Prime Minister says the country will negotiate with US President Donald Trump over his tariff plans once Canada is “shown respect” as a sovereign nation.

Trump has risked a major diplomatic crisis with the US’s northern neighbour over his threats to impose significant import tariffs and his repeated suggestion that Canada could become America’s 51st state. His tariff plans have sparked concerns of a major trade war between the two global superpowers. Earlier in March, William’s father, King Charles, also showed subtle signs of support as he welcomed officers from the Canadian parliament to Buckingham Palace.

His Majesty held an audience with Gregory Peters, who is Usher of the Black Rod of the Senate of Canada, and Senate Speaker Raymonde Gagne on March 12 in the afternoon.

While such audiences with the King are private, they are understood to have discussed these vital matters in hand. The audience was held to present Mr Peters with a new ceremonial sword commissioned by the Senate in the King’s honour to mark the change of reign.

In February, on the 60th anniversary of Canada’s flag day, the King appeared to send another subtle message of support to the nation, writing: “On February 15, 1965, the red and white maple leaf was first flown on Parliament Hill in Ottawa.

“Since that time, it has become internationally recognised as a symbol of a proud, resilient and compassionate country. For my own part, it is a symbol that never fails to elicit a sense of pride and admiration, as I recall with the deepest affection my many Canadian visits and friendships.”

The Prince of Wales arrived in Estonia for the start of a two-day visit to bolster ties with Tallinn which began Thursday. William has tavelled to Estonia predominantly in his role as colonel-in-chief of the Mercian Regiment – which is taking over NATO defence duties in the country from the Royal Dragoon Guards.

Prince William began his trip by sitting down for talks in the capital Tallinn with Estonia’s president, Alar Karis, who has been prominent among those giving military equipment and political support to Ukraine.

On the second day of his visit, the royal will travel to attend a handover ceremony at the Tapa army base, which houses the UK’s largest permanent overseas deployment. There are around 800 British service personnel in total in Estonia.

The prince founded his Earthshot Prize to help recognise and scale up solutions to repair the planet, and while he is in the country he will also attend an event to learn about renewable energy startups.