Co-hosts Australia are in the last four for the first time but will have strong backing in Sydney's 81,500-capacity Stadium Australia on Wednesday.

"That is a different thing to cope with," said Walsh.

"But they are a great team, whether they feel the pressure or not. The way they play, they don't look like they feel it.

"They are very physical and we have to be ready for that. It's just about going in confident and playing on the front foot.

"When you're playing against it and can quieten the crowd, it's a nice feeling. There's positives and negatives to both [sides]. We experienced it against Colombia in the quarter-finals."

The Matildas' success has been celebrated across Australia with thousands of fans pouring into the streets of Sydney and in fan parks to watch their games on big screens.

Overnight viewing figures reported the quarter-final win over France was Australia's biggest television audience for a sporting event in more than two decades - since Cathy Freeman won gold at the Sydney Olympics in 2000 - with an average of 4.23 million.

National newspapers have been building up the sporting rivalry between Australia and England which was felt during the Ashes and the Netball World Cup.

But Walsh says there is no added incentive to beat Australia.

"The media do talk a lot but for us it's not about Australia, we want to win regardless," she said.

"There's a rivalry in any team, it doesn't make any of a difference if the media is talking about beating England.

"Whatever game we play in we want to win, it doesn't matter who you are playing against. We aren't thinking about spoiling the party. We are fully focused on reaching the World Cup final."

Williamson's support a 'massive boost'

England's Euros-winning captain Leah Williamson, who was ruled out of the World Cup with an anterior cruciate ligament injury, flew out to Australia to support the Lionesses in their quarter-final win over Colombia.

"It's a massive boost for the team to see her supporting," said Walsh.

"It's the other side of the world, it's not an easy flight and that shows what she feels about this team.

"The first time I saw her she was outside my hotel window waving. She didn't want to distract us on game day.

"It was nice to get the win and celebrate after. I can imagine it's not easy for her to watch, she would have wanted to be playing, so we appreciate her support.

"It shows what a good character she is to be able to that for us."

Leah Williamson (in hat) posted a picture on Twitter from the stands after England's victory over Colombia

'This is next level - it's a different game'

Matildas midfielder Tameka Yallop says it has been "special" for the Aussie nation to join the team on their journey at the World Cup.

"We've been kicking a ball a long time. We did it in our back yards with no-one watching and then, when we all put on our first Aussie jersey, there weren't that many people watching," said Yallop.

"But we were still playing and training as hard as we always have been. To put in all that hard work and for people outside our circle to be on that journey with us is something we haven't experienced to this extent.

"Every Matilda that puts on the jersey feels the legacy of the players before and this tournament has built on that and grown the excitement for future generations."

The last time Australia faced England, in a friendly in April, they ended the Lionesses' 30-game unbeaten run under manager Sarina Wiegman.

But Yallop says it is a "completely different" scenario going into the semi-final and their previous victory does not give them a psychological edge.

"This is next level. It's a different game," she added. "That was a friendly and we did take something out of it. Now, we're into the knockout games at the World Cup and it's completely different.

"We won't let that result get in the way or alter our tournament mode."