The 23-year old Welshman continues to produce consistently brilliant performances for both Spurs and Wales and is sure to again attract the interest of bigger clubs in England and around Europe.
"I think (Champions League will keep him here). This is where most of the clubs want to be, and where most of the players want to play," said Villas-Boas.
"Gareth's future is intimately related to what the objectives that we achieve for the season.
"Hopefully qualifying for the Champions League means we can attract better players and continue to hold on to our best players.
"It is difficult for other teams with the economic situation as it is to buy a player of this dimension.
"At the moment we are very, very fortunate to have him and I think we can reach our objectives with him at this level. If we reach our objectives we can hopefully continue to have Gareth in our club."