The 21-year-old has flourished for Spurs this season, winning PFA Player of the Year as well as drawing rave reviews for his performances in the Premier League and Champions League.
But Tottenham's 1-0 defeat at Manchester City on Tuesday means the north London side will miss out on a place in Europe's elite competition next term, raising questions over the futures of a number of their top players including Bale, Rafael van der Vaart and Luka Modric.
Euro star: Gareth Bale is one of the most highly-coveted stars on the Continent following his sparkling displays in the Champions League this season
And with Europe's top clubs including City, Inter Milan and Real Madrid interested in the speedy winger Speed thinks it's crucial for his game that he is playing at the best level he can when he returns from his ruptured ankle ligament damage in around ten weeks time.
He said: 'I reckon it's important for all the players to play as high as possible and Champions League football is a place where Gareth has shined this year, and the more you play on the world's biggest stage the better.
'I was linked here, there and everywhere and it's down to gut feeling and belief what you think is best for yourself.
'Tottenham making it to the Champions League this season would have made that decision easier for him but I'm sure Harry wouldn't want to lose him in anyway shape or form.
'It's all down to the player and his individual preferences at the time.'
Missing out: Bale will not play in the Champions League next season if he stays at Spurs
Speed who was appointed Wales boss last December also stressed the importance of all his players playing for thenational team to feature at the highest level they can.
'It counts for all the players, if Wales are going to achieve anything and be successful we have got to be a team - and it's all about the team. So the more players we can get playing at a higher level the better,' he added.
The sale of Bale could have greater ramifications for the club with boss Harry Redknapp threatening to walk out if his best players are sold.
Redknapp said recently: 'If you start thinking about selling your best players you might as well give up. What's the point in carrying on? It effectively sends out all the wrong signals.
'And when one player leaves the rest want to follow him straight out the door. Then you have situation where the quality of football goes into decline and you're going backwards on the pitch.'
Back to school: Wales boss Gary Speed takes a training session at St John's C of E Primary school
Bale himself has refused to rule out a White Hart Lane exit, previously stating that he has no qualms over moving abroad.
He said: 'If a great opportunity arises you need to seriously consider it. I left home at 15. If I leave the Premier League, I'll learn another language, I'll know other people, another country, I will grow as a person.'
However any potential suitors for the former Southampton player could be put off by the Welshman's injury problems.
Bale has yet to play a full campaign since joining Tottenham in 2007 and he will miss the remainder of this campaign with the club not expecting him back until pre-season.
Gary Speed is an ambassador for the npower Football League Under 11 Kids Cup and was speaking from Barnet, where the 41-year-old was coaching team members of St John's C of E Primary School, who will be representing their local Football League club Barnet FC, in the League 2 Grand Final at Old Trafford on 28th May 2011. Bale out with ruptured ligament but Spurs sure he'll be fit for new seasonI'll quit! Redknapp promises to resign as boss if Spurs sell his starsEXCLUSIVE: Speed hopes Giggs will continue involvement with Wales campAll the Tottenham news, features and opinion
Explore more:People: Gary Speed, Harry Redknapp, Luka Modric, Gareth Bale Places: London, Wales, Europe