LONDON: Arsenal manager Arsene Wenger has slammed the Dutch federation for minimising the seriousness of the ankle injury which is set to keep highly-valued striker Robin van Persie out for up to five months.

Van Persie was on Saturday told he needed reconstructive surgery on ankle ligaments, which he injured playing for his country in a recent friendly, and would not be fully fit for between four and five months.

The news came as a surprise as Arsenal initially believed he could return in six weeks. A scan by a leading ankle injury specialist revealed that more damage has been done than first thought.

Wenger said the Dutch federation (KNVB) downplayed the extent of the injury and kept the Gunners in the dark.

Quoted in several national newspapers, Wenger said: "I think the Dutch FA minimised the injury.

"We have just found out that it is much worse than what they told us. If a player gets injured with his country he should be sent back to his club straight away to be checked out by their doctors, not by those of the national team.

"Countries just take your player away for a friendly and then give him back and say: 'There you go'. It doesn't happen in any other sport. It's a joke and is so disrespectful."

Van Persie, who with seven goals is the London club's top scorer so far this season in the Premier League, suffered torn ankle ligaments during the Netherlands' goalless draw against Italy in a friendly ealier this month.

He will undergo surgery in Amsterdam next week and is expected to be sidelined for up to five months.

"In order to repair his ankle, Robin will undergo surgery next week in Amsterdam to reconstruct the ligaments," said a statement from Arsenal.

"The club's medical team anticipate that a full recovery will take between four and five months."

Van Persie's absence will prove a massive blow to the Gunners, who face leaders Chelsea on Sunday knowing that defeat would leave them trailing the Blues by 11 points.