"May you roar to victory," King Charles said in a social media post ahead of Sunday's match.

The King and Queen are set to be among the 13 million Britons expected to tune in for the historic game, which kicks off in Sydney at 11am UK time today.

A Buckingham Palace source said: "Both Their Majesties will be following Sunday's events with the greatest interest."

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England men's boss Gareth Southgate followed the monarch in offering his best wishes to Sarina Wiegman's team, aiming to become England's first World Cup-winning footballers since 1966.

But he admitted he had "no advice" to offer a team that has accomplished what his has not.

Speaking in a video posted on the Lionesses' social media, Southgate said: "Hi to you all out there in Australia. You're doing a brilliant job, so that's the first thing, and of course there is no advice because you've done more than us already, and you know what is needed to win.

"So all that remains is to wish you the very best for the final, and we hope you can bring that trophy back. Good luck everybody."

His sentiments were echoed by England men's captain Harry Kane, who during the tournament completed a £100m move to Bayern Munich.

He said: "Hi Lionesses, I just wanted to say best of luck for the World Cup final on Sunday. I'll be watching.

"Amazing journey so far, you should be really proud of yourselves. We're all behind you, all supporting you, we know you can do it, so go and get that World Cup win and bring that trophy home. All the best."

'You've made us all proud'

In other messages of support, Prime Minister Rishi Sunak said "you've made us all proud".

"Whatever the result, I want you to know that you have secured a lasting legacy," he said.

"That every girl in this country will have equal access to all school sport, including football."

Mr Sunak said from being crowned European champions at Wembley last year, to their dramatic campaign in Australia this summer, the squad had made young girls "feel they belong on the pitch".

"So, in a way, you've already brought football home," he said, referencing the popular England anthem.

"All that remains is to bring the trophy home too - and the whole nation is rooting for you."

Labour leader Sir Keir Starmer echoed similar sentiments in his letter to the Lionesses as he told them that "everyone back in England is with you all the way".

Sir Keir said: "No matter what happens on Sunday, the whole country will always be grateful to you for ensuring a generation of youngsters walk taller and prouder.

"Just as for previous games we will be tuning in as a family, kicking every ball while trying to keep a lid on our nerves. Millions of households will be doing the same."

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Experts are predicting the match could shatter previous viewing records for a women's football match, which included an average audience of 11 million for the Euros final in 2022 against Germany.

With Levelling Up Secretary Michael Gove being forced to write to local councils to ask them to do "everything they can to help pubs get open earlier on Sunday", it is thought most will stay home to watch the game.

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William and Charlotte's good luck message

Mr Sunak has opted not to travel to the match and will be among those watching from home, with the foreign and culture secretaries to represent the government at Stadium Australia.

None of Britain's royals will be there, either, with Prince William issuing an apology.

The prince has come in for particular criticism because he is the president of the Football Association (FA).

"Sorry we can't be there in person," he said in a video on Saturday, joined by daughter Princess Charlotte.

The young royal said in the clip: "Good luck Lionesses!"

William wished the team "huge good luck" for the match, saying his family are "so proud of everything you have achieved and the millions you have inspired here and around the world".

Women and girls around the country celebrate progress

As the Lionesses take to the field, they will be backed by hordes of women and girls rooting for their heroes, with many celebrating the progress that has been made since their parents and grandparents were denied a chance to play the game.

One fan, 70-year-old Gail Newsham, says she can't wait to see the team take to the pitch, after growing up at a time when women were banned from the sport.

She told the AP news agency: "I'll be wearing my shirt, I'll be having a sausage roll and a glass of bubbles. That's what I've done every match, so I'm going to do it again on Sunday and just, you know, cheer the girls on."

Ava, 10, is just one of the young girls inspired by the Lionesses.

The young footballer, whose favourite player is injured captain Leah Williamson, told Sky News she was "nervous" about the final and there would be "big cheers" if England won.

"I see them as people I want to become," she said.

"It's inspirational how women who used to not be able to do a lot of stuff have climbed up the mountain to become the best they can be."

England boss Wiegman has said her players are hoping to play their "best game ever" to bring the trophy home.

She said: "We felt the support, we felt the support here, but also from the other side of the world in the UK. That's something that we dream of."