Kevin Pietersen's ongoing fitness concerns will reportedly rule him out of England's Test series with New Zealand.

The 32-year-old batsman missed the final match of England's away series against the Kiwis last month with a knee injury that is taking longer to heal than originally anticipated.

Medical staff are expected to advice Pietersen to sit out the reverse series against the Black Caps, but he will not need surgery that could have kept him out of the Ashes in July.

The former England captain's injury has already prevented him from representing Delhi Daredevils in the Indian Premier League this month.

England have two Tests against New Zealand this summer, the first of which starts at Lord's on May 16.