AUSTRALIA boss Pim Verbeek insists that Newcastle United are considering summer surgery for Mark Viduka as the striker continues to be plagued by a niggling Achilles problem.

The 32-year-old will be available for United's remaining Premier League games against Chelsea and Everton. However, a minor operation will almost certainly rule Viduka out of Australia's four World Cup qualifiers in June.

Verbeek last night revealed that the former Middlesbrough striker is likely to miss the two games against Iraq, as well as other Group One clashes with Qatar and China.

Viduka has started the last seven games for the Tynesiders, although Verbeek revealed: "He is struggling with an Achilles problem. Newcastle are thinking of rehab, having injections and maybe a small operation at the end of the season so I don't think he will be available.

"He was struggling and when we spoke he said he would see if he is better and we would find out if he would be available, but it is not going very well for him.

"It will be very difficult for him to be part of the group."

Viduka's first season at St James' Park has been plagued by several injury setbacks, which have restricted him to 27 appearances.

However, Viduka has made an impressive contribution when fit, scoring seven goals.

Kevin Keegan, who claimed last week that surgery would not be required, hopes Viduka will be able to play a more prominent part in his plans next season.

The striker will be available to face Champions League finalists Chelsea at St James' Park on Bank Holiday Monday, when a Newcastle win would all but end any hopes Avram Grant's men have of landing the Premier League title.

Nicky Butt was part of the Newcastle side that scuppered Chelsea's hopes of retaining the championship last season following a goalless draw at St James' Park.

It was a result that put Butt's former club Manchester United in the driving seat to reclaim the title, prompting several texts from his old team-mates at Old Trafford.

But, while the midfielder would like to do the same again this year, his primary focus is to help Newcastle continue their recent good run of form and end the season on a positive note.

He said: "I'm sure it will be the same again and the texts will come flying in but obviously they have their own things to look at and their destiny is still very much in their own hands.

"It's most important that we do it for ourselves to make sure that we finish the season strongly."

Butt is confident that, after previous false dawns, the club is making the right progress under Keegan.

"I'd like to think there are exciting times ahead for this club next year but every year seems to be the same at this club," said Butt.

"We say next year, next year but we've got the right people in place now, the right manager and right coaching staff and obviously we have got some good players.

"We need to add to that and then we'll be able to really look forward to it."

Meanwhile, Newcastle duo James Milner and Emre are continuing to step up their fitness after playing in a practice match on Wednesday. Defender Claudio Cacapa was also involved.

Milner is back in full training following a foot problem, while Turkey international Emre, who has not played since February after injuring his ankle, is close to full fitness. The pair should be included in the squad to face Chelsea.