Glory captain Taggart penned a new one-year deal with the club on May 29, but is now set to join Vietnamese club Hanoi FC, coached by Socceroos legend Harry Kewell.
Initial reports stated Taggart had been told by Perth he was no longer required at the A-League club.
But Glory have refuted that claim, with the club's football director Stan Lazaridis saying it would have been wrong to stop the star striker leaving given the lucrative deal on offer.
"With a big offer having been tabled for him personally and in the light of the outstanding service that he has given Perth Glory both on and off the pitch, it would have been wrong for us as a club to stand in his way," Lazaridis said in a statement.
"Contrary to some of the inaccurate reports that appeared overnight, this is very much a mutual and amicable parting of the ways.
"'Taggs' is Glory through and through and will always be a legend at this club."
Taggart's move still isn't 100 per cent certain, with the 33-year-old needing to pass a medical first before the deal is confirmed.
News of Taggart's impending move will come as a huge shock to Glory supporters, especially so soon after the fan favourite had re-signed.
Taggart's 61 goals for Glory are the most for the club in the A-League era.
The former Socceroos striker had previously said it would be an utter disaster if he finished his career without leading Glory to title success.
"I believe it's well understood how much I love this place, but after mutually agreeing with the club, we both agree it's the right time to move on," Taggart said in a statement on Friday.
"I am looking forward to seeing some young boys step up and supporting from afar.
"I leave grateful for the incredible support and wish nothing but the best to you all."
Taggart's exit comes just over a month after Professional Footballers Australia slammed Glory for a series of late payments to players and staff.
Glory, owned by property developer Ross Pelligra, made late payments in July last year, as well as June and July this year.
A club spokesperson attributed the late payments to "timing issues", but it raised major red flags at PFA, who labelled the situation "unacceptable".
Meanwhile, Brisbane Roar have signed Australian midfielder Tyrese Francois on a multi-year deal.
The 26-year-old moved to London as a junior and came through the Fulham academy, going on to make his first-team debut for the club in the Premier League.
Loan spells at Croatia's HNK Gorica and Denmark's Vejle Boldklub followed, and he most recently played for Wigan Athletic in England's League One.Â