Cowboys and Fiji forward Tariq Sims says his side will take a moment to soak up the enormity of its achievement in reaching a World Cup semi-final before preparing for an Australian side packed with superstars.

"I'm very excited, I'm a bit lost for words at the moment. I don't know how to describe the feeling that I'm feeling right now," Sims told Cowboys TV following Fiji's 22-6 quarter final win over Samoa.

"Australia, that's a different machine, it really is. They've got superstars all across the paddock. It's up to us to come up with a game plan and execute that and take them down."

Playing a semi-final against the Kangaroos at Wembley will be among his career highlights, Sims said, adding that he needs to work on getting the penalties out of his game before that match after conceding three against the Bati.

Watch the full interview with Tariq Sims at cowboys.com.au.