Levy fought a protracted battle with Chelsea last summer to keep star playmaker Luka Modric at the north London club and speculation is rife that the Croatian, and winger Gareth Bale, will be the subject of strong interest again this summer.
Bale added fuel to the rumours linking him with Barcelona earlier this month when he declared he would consider his future if Spurs failed to make the Champions League, while Manchester City boss Roberto Mancini has spoken in glowing terms about Modric.
Tottenham manager Harry Redknapp insists the club will end up going backwards if they sell their top players and Levy agrees.
The Spurs chairman wrote in his end of season address to supporters: "Our squad has top players at all levels and we shall continue to seek stability and to retain key players this summer and beyond.
"We are a club that is focusing on growth and moving forward."
Spurs finished fourth in the Barclays Premier League after beating Fulham 2-0 at home in their season finale at White Hart Lane on Sunday.
Ordinarily, that would ensure Champions League qualification, but that will not be the case if Chelsea beat Bayern Munich in the European Cup final on Saturday.
Levy insists this has been a progressive season, however, given that Spurs finished fifth last term.
"Today [Sunday] will see the final league positions of several clubs decided, ourselves amongst them," Levy continued.
"We may, however, find that we still have to wait on the outcome of the Champions League final next weekend to know in which European competition we shall be competing.
"It is a mark of our progress and the quality of our squad that each season we now look and expect to be competing at the top of our game.
"Once again we have seen football played at home and away which has shown our brand and style of play around the world and led our competitors to describe us as the most entertaining team in the Premier League."
Tottenham have undergone an eventful season off the pitch as well as on it.
Redknapp underwent a heart procedure in November and successfully defended himself in court against two charges of tax evasion, while White Hart Lane witnessed the horrific on-pitch cardiac arrest of Bolton midfielder Fabrice Muamba in March.
"We are grateful for the positive outcome on all these matters," Levy added.
This season has also seen Tottenham make progress in their plans to build a new stadium adjacent to their current home in north London after failing in their bid to take over the Olympic Stadium.
"With a commitment to invest in the area around the stadium from the Mayor and Haringey Council, an investment of some £90m in land and planning by the club and with planning applications granted, we are now pushing ahead with what is widely acknowledged to be the single most important development capable of delivering social change in the area - an iconic new stadium at the heart of a true sport-led regeneration scheme, delivering new homes, shops, restaurants, jobs and opportunities," Levy added.
"The scale of demolition around the stadium should leave no one in any doubt as to our intent to forge ahead with this project and we shall devote our full attention and energies to it."