Flintoff missed the first two Tests because of his ankle problem

The all-rounder, who missed the first two Tests against West Indies because of the condition, experienced pain after a fitness test on Tuesday.

The injury, although also in the left ankle, is said to be separate from the bone spur problem he had last summer.

On that occasion he missed three months but England hope he could return to action more quickly this time.

Dr Nick Peirce, England and Wales Cricket Board chief medical officer, said: "Despite intense treatment and rehabilitation with England and Lancashire's medical teams, Andrew's ankle has continued to cause him discomfort when bowling at full capacity.

"As a consequence he will undergo an exploratory arthroscopy on his left ankle over the weekend."

FLINTOFF'S INJURY WOES 1999 Returns early from South Africa with broken foot 2000 Back injury ends Pakistan tour 2002 Hernia operation and later returns from Ashes tour with groin problem 2003 Misses Zimbabwe series with shoulder injury 2005 Ankle surgery in January 2006 Out for 12 weeks after ankle surgery 2007 More surgery to left ankle

"A comprehensive timescale of rehabilitation will be clearer following the operation.

"This current ankle injury is separate to the previous posterior impingement injury so the recovery period is not expected to be as long as Andrew's previous surgery."

Flintoff, who also underwent ankle surgery in January 2005, will hope to get fit for the Test series against India, which begins on 19 July at Lord's.

But the one-day series against the same opposition, starting on 21 August, may be a more realistic target.

Flintoff said: "Obviously I'm bitterly disappointed to face another operation on my ankle as I really thought I was making progress with the injury over the past few weeks.

"I've been working really hard on my game and the rest and rehabilitation appeared to be helping the ankle but after giving it a strong workout this week, it now seems that an operation is the only option.

"Having bounced back from ankle surgery before I know how much work is ahead of me but I'm desperate to get back playing for England and determined to overcome this setback as soon as possible."

606: DEBATE Discuss Flintoff's injury problems

Flintoff had ankle surgery for the second time on 27 July 2006, and when he made his international comeback on 15 October - against India in Jaipur - he played as a batsman only.

The all-rounder struggled with the bat all winter, however, and will probably need to be fit enough to bowl at 100% before he next plays for England.

The operation he will have at the weekend will pinpoint the exact nature of the injury, and indicate what further treatment is necessary.

One of the UK's leading arthroscopic surgeons, Simon Moyes, said: "MRI scans miss up to 20% of problems within the ankle joint.

"His proposed ankle arthroscopy is, from a diagnostic point of view, virtually 100% accurate.