By Anna Thompson

Pietersen is in England's squad for Zimbabwe

England one-day batsman Kevin Pietersen has left Nottinghamshire after turning down a lucrative three-year deal.

Pietersen, in England's squad for the Zimbabwe tour, told BBC Sport he has had offers from four counties.

The South African-born star wanted to leave last winter but eventually saw out the remainder of his contract after a six-month stand-off.

"I had four fantastic years at Notts but I need a new challenge because I felt I was in a comfort zone," he said.

The 24-year-old added: "For purely cricket reasons, I felt the time had come for me to move on. When you go to a new county you have to prove yourself again and this will be good for my game."

Pietersen will tour Zimbabwe with England next month and is currently getting fit for the series at Loughborough University with the England Academy.

I will always be grateful to Notts for bringing me over from South Africa and for supporting me Kevin Pietersen

He said although the new Notts deal was lucrative, money was not a motivation.

"Money is not a huge issue for me," Pietersen said.

"If I do well in my cricket career, the money is going to come."

Pietersen has made more than 5,000 first-class runs at an average of 54 during his career.

He had hit 18 centuries, four of which came this summer, to help Notts' promotion to Championship Division One.

Pietersen added: "I will always be grateful to Notts for bringing me over from South Africa and for supporting me. I wish them all the best for next season."

Pietersen would not confirm which counties were vying for his signature but he said he had had four offers from Division One sides.

Notts' director of cricket Mick Newell said he was extremely disappointed to lose a man of Pietersen's ability.

Newell said: "We offered him a new three-year deal on a considerable salary which would have maintained his status as one of the highest-paid players at the club but he has chosen not to accept it.