Australia captain Michael Clarke: England weaker without Kevin Pietersen

Australian cricket captain Michael Clarke. Credit: PA

Australia captain Michael Clarke believes England will be weaker without Kevin Pietersen this summer - but expects his side to have a tough job on their hands if they are to retain the Ashes.

Pietersen scored an unbeaten 355 in Surrey's County Championship clash with Leicestershire last week, but his hopes of earning an England recall were dashed when newly-appointed England and Wales Cricket Board director Andrew Strauss confirmed he would not be considered for this summer's five-Test home series against Clarke's side.

Strauss declared a "massive trust issue" between himself and Pietersen - England's leading run scorer across all three formats - prevented him from ending the South Africa-born batsman's 15-month international exile, but Clarke thinks that decision is a mistake.

Australia play two Tests against the West Indies before the first Ashes Test gets under way in Cardiff on July 8 and Clarke, who guided Australia to the 5-0 Ashes whitewash in 2013-14 which led to the end of Pietersen's international career, confessed to mixed feelings about the 34-year-old's latest exclusion.

"There's probably two sides for me," he said. "There's the personal side where I feel for KP because I get on well with him and I'd love to see him back playing cricket for England.

"His form has been outstanding, he's still a great player and I know he wants to play, so I feel for him on that side.

"The other side (is) we go there soon to play against England. Any team without Kevin Pietersen in it I don't think is as strong.

"His statistics speak for themselves. He's been a wonderful player over a long period of time and he's obviously still in career-best form."

Australia's vice-captain Steve Smith recently declared that England would not "come close" to victory against Darren Lehmann's side but Clarke, who guided the Baggy Green to their fifth World Cup title in March, has warned his team-mates against complacency.

"Playing away from home is your greatest challenge as an international sporting team and England will be tough," Clarke said.

"When we get there, no matter what 11 players they put on the field they're going to be really tough (because) they know their conditions well.

"As are West Indies, and it's really important we stay focused this West Indies tour and have some success there."