Shoaib has taken 165 Test wickets and 199 in one-dayers

"The specialist will remove floating bodies in both his knees. It is a clean up," said Pakistan Cricket Board spokesman Saleem Altaf.

"Shoaib will require a minimum six to eight weeks to recover, after which he can resume training."

The 30-year-old does, however, have a degenerative arthritic problem which may require further surgery in future.

Shoaib had already been ruled out of a tour to Sri Lanka in April because of a stress fracture in his ankle.

Now his priority is to regain full fitness in time for a Test and one-day series in England from July to September.

He has been beset by fitness problems throughout his career but played a pivotal role when Pakistan beat England 2-0 on home soil at the end of last year.

It took its toll, however, and he was less successful during a recent home Test series against India.

"Shoaib bowled in pain in the Test matches on generally flat pitches and he has taken a lot of pounding on his ankle and knee, which has led to the problem," said Altaf, Pakistan's Director of Cricket Operations.

Meanwhile, Pakistan have been told seam bowler Shabbir Ahmed cannot be reassessed by the International Cricket Council until Decmber.

The 29-year-old is currently serving a 12-month ban because of an illegal action, but has been working to re-model it with former Pakistan Test player Sarfraz Nawaz.

Shabbir hoped it could be reviewed before the tour of England but ICC General Manager David Richardson said this will only be possible once the ban has been completed.