OTTAWA - Jack Layton will not attend a special NDP caucus retreat to plot strategy for next month's resumption of Parliament.

But the ailing NDP leader still hopes to be in his front-row seat by the time the House of Commons gets back to business on Sept. 19.

Layton has been on a leave of absence since July 25, forced to take time off to fight a second -- and evidently much more serious -- bout with cancer.

He's vowed to back on the job by Sept. 19.

But his spokesperson Kathleen Monk says there was never any plan for Layton to come back sooner to prepare for the fall parliamentary session.

Nor was there ever any intention of his taking part in the pre-session caucus retreat, over which Layton's hand-picked interim leader, Nycole Turmel, will preside.

"Layton said in July that he intends to return to Parliament on Sept. 19 when the House of Commons resumes," Monk said Wednesday.

"Our caucus retreat is being held Sept. 13-15 in Quebec City. Therefore, there were no plans for him to attend that meeting."

Layton was diagnosed with prostate cancer 18 months ago and underwent surgery to repair a fractured hip just weeks before the May 2 federal election. Despite his health woes, he campaigned vigorously in the spring campaign, taking his party to a historic 103 seats and official Opposition status.

However, he was diagnosed with a new form of cancer last month. He would not specify what kind of cancer or discuss his treatment or prognosis during a news conference announcing his decision to step aside temporarily. But his emaciated appearance and raspy voice shocked the country.

Despite his vow to return to work next month, many New Democrats have urged Layton to take as much time as he needs to recuperate.