Giggs future in Van Gaal's hands as Rio shown door
Interim boss open-minded about playing on but Ferdinand says his goodbyes to United
Rio Ferdinand has already been told that he will not be offered a contract by the Dutch coach.
With Ferdinand's contract due to expire next month, the former England captain knew United had no plans to keep him beyond this summer.
In a statement on his website, he said: "I have thought long and hard over the last few months about my future and after 12 fantastic years playing for what I regard as the best club in the world, I have decided the time is right for me to move on.
"I joined Manchester United in the hope of winning trophies and never in my wildest dreams could I have imagined how successful we would be during my time here.
"There have been so many highlights, playing alongside some great players who have become good friends, winning my first Premier League title and also that fantastic night in Moscow are memories that I will cherish forever.
"Circumstances didn't allow for me to say goodbye the way I would have liked, but I'd like to take this opportunity to thank my team-mates, staff, the club and the fans for an unbelievable 12 years that I'll never forget.
"Winning trophies I dreamed about as a kid came true at this great club.
"I am feeling fit and healthy, ready for a new challenge and looking forward to whatever the future holds for me."
Ferdinand's departure is no surprise, with his exit widely expected.
But Giggs remains open-minded about playing on, admitting it would be "difficult" to retire from the game.
Holland coach Van Gaal is expected to be confirmed as United manager before the Dutch face Ecuador in a friendly in Amsterdam on Saturday, with both parties keen to resolve coaching appointments before the 62-year-old is finally installed as David Moyes' successor.
Giggs (40) made his 963rd senior appearance for United against Hull last week – although this was the first season in Premier League history in which he failed to score – but admits he is still undecided about whether to continue as a player.
"First of all, does the new manager want me?" Giggs said. "But also, do I want to put my body through another year? Do I want to continue eating the right things or face another pre-season?
"Do you want to go out still enjoying it and not go on a year too long? These are all things I have got to consider. But I think it will be difficult to stop playing and it is probably easier when you have had injury problems.
"I have seen players who just cannot go on and they are not training, but I have never really had those problems, so I have got to weigh up a lot of things."
United, meanwhile, are awaiting a response from Southampton after lodging a bid of £27m for England left-back Luke Shaw at the weekend.
With Chelsea and Manchester City understood to be pursuing other options, United are hopeful of concluding a deal for Shaw before the World Cup, although he is likely to be behind Leighton Baines in England's starting line-up. (© Daily Telegraph, London)