Joe Root feels England are in uncharted territory where there are "no question marks" surrounding their final 15-man squad heading into the World Cup.

England's previous campaigns have been characterised by last-minute changes in roles or even personnel though there is a consensus that the build-up to this tournament on home soil has been relatively straightforward.

For different reasons, there were three amendments to their line-up from the preliminary party that was announced last month, with Jofra Archer, Liam Dawson and James Vince replacing David Willey, Joe Denly and Alex Hales.

Root believes the trio that have forced their way in highlights the strength in depth available to the number one ranked one-day international side in the world, who are favourites to land their first global 50-over trophy.

Root told Sky Sports News: "It's a very unique situation here where you've got so many guys that have performed brilliantly. You look at the squad, we're going into a tournament where there's no question marks.

"Everyone deserves their place, has performed consistently well going into it and it's a brilliant place to be.

"It is bitterly disappointing (for those left out) and it was always going to be tough on someone but it shows the strength in depth within the group, where we're at as a one-day team at the minute.

"It shows how well we've prepared and that we've given ourselves the best chance leading into it.

"We've worked really hard to deserve the tag of number one ranked team going into the tournament. We should enjoy that, we should get a lot of confidence from that and really embrace that."

England begin their campaign on May 30 against South Africa at the Oval while their group fixture against Australia at Lord's on June 25 is noteworthy.

Australia were whitewashed 5-0 by Eoin Morgan's side in last year's ODI series in England although their squad has been bolstered by the returns of former captain Steve Smith and his deputy David Warner.

The pair have recently completed 12-month bans for their roles in the ball-tampering scandal in South Africa which blighted Australian cricket last year.

Root is aware Warner and Smith face hostile receptions in the upcoming weeks but is wary of the batting duo.

England's Test captain added: "They've got two of their best players back playing.

"I'm sure they'll get a number of different receptions over the next couple of weeks but it's good that they're back playing.

"We want to play Australia and we want to beat Australia's strongest side, those two are definitely in that."