Spurs chairman Daniel Levy resisted a £40m bid for Modric last summer from Chelsea but will now listen to offers for the Croatian playmaker, who said last week that he would make a decision on his future after Euro 2012.
Manchester United have made Modric their top transfer target but will struggle to meet Tottenham’s asking price, with Levy adamant the 26-year-old will not be sold on the cheap and ready to ask for £40m for the central midfielder.
Chelsea and Manchester City have also been linked with Modric while reports in Spain over the weekend suggested Real Madrid manager Jose Mourinho is weighing up a move for the former Dinamo Zagreb man.
Spurs would prefer not to strengthen a domestic rival and would be more open to selling Modric abroad if, as expected, the Croatian seeks a move away from White Hart Lane for the second successive summer.
Modric has not signed a £100,000-a-week contract offered by Tottenham and was told last year that the club would not stand in his way if they failed to make the Champions League. He is under contract until 2016, but has publicly spoken of his desire to play for a bigger club and compete for trophies.
Bale, meanwhile, has previously suggested that he would consider his future if Spurs failed to make next season’s Champions League amid interest from a number of top European clubs including Real Madrid and Barcelona.
Barcelona, in particular, have made the Wales winger a leading target for the summer but Tottenham informed the Catalans in writing last week that the 22-year-old is not for sale.
Sources have told Goal.com that it would take a “stunning” offer - in excess of £50m - for Spurs to reconsider their position on Bale as Harry Redknapp’s side look to challenge for a top four finish again next season.
Asked about the interest from the Spanish giants earlier this year, Bale said: “If you said to any young player that you could play for Barcelona or Real would they turn it down? Probably not.
"It's a bit like Harry [Redknapp] and England, it's a once-in-a-lifetime dream. If a bid was accepted you would obviously have to seriously consider it.”
Although Spurs are relatively relaxed about the future of a player who is tied to the club until the summer of 2015, they know that his value will begin to depreciate from next season if he does not extend his deal.
Redknapp has warned that Spurs must keep their stars to remain competitive.
“Once you start selling your best players you're finished," the White Hart Lane boss said earlier this month. “I don't know why Tottenham should be seen as a club that will sell its best players. We are not looking to sell our best players. We are looking to build a team here, not dismantle. “The chairman made a stance with Modric last year - the stance was that we are looking to build, to add to the group we've got and improve for next year, not to go backwards. “If we go backwards, we're going nowhere basically are we? We will slump back into mid-table mediocrity and we don't want that.” Meanwhile, Spurs have still not reached an agreement over a transfer fee for Ajax captain Jan Vertonghen after a day of talks in Amsterdam on Monday.
Levy has returned to London and is confident of reaching an agreement, despite the Dutch giants' £12.1m asking price. The Belgian defender is ready to submit a transfer request to force through the move having already agreed personal terms with the Londoners.