Warren Gatland’s side face the English at Twickenham on Sunday, 11 August, in their first exhibition match before the tournament in Japan, which starts on September 20.
After an impressive record 14 wins in a row, including claiming the coveted 2019 Six Nations title, Wales are among the favourites to lift the famous Webb Ellis Cup in the rugby betting.
However, England remain favourites on their home turf to claim a victory over their British rivals this weekend, with 888sport pricing Eddie Jones’s side at 2/5.
Williams – who won 87 caps in a glorious international career for Wales – has urged the new generation of Welsh stars to show self-belief in their upcoming games.
Speaking via the BBC, Williams said: “You’ve got to talk yourselves up sometimes.
“Perhaps the likes of Australia, New Zealand aren’t playing particularly well, but that doesn’t matter for those guys.
“They will certainly turn up and be one of the favourites for the cup, but as far as Wales are concerned they’re in quite a weird situation for Wales.
“We’ve been targeted as one of the favourites for the World Cup and never been in that position before as a nation.
“But I think it’s great. I think the players, squad and coaches we have at the moment need to be a little bit more confident and need to be a little bit more arrogant about how good they can actually be going into this World Cup because it will give them massive confidence.
“That’s why a lot of these games prior to the World Cup are so important.
“You’re playing England and Ireland, potential World Cup winners and some of the best teams in the world.”
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