However, Tew said there were many other ways to keep players in New Zealand.
Key All Blacks, including Highlanders fullback and captain Ben Smith, are coming off contract next year and are believed to have received some significant offers from overseas clubs.
Also coming to the end of deals with the national union are backs Aaron Cruden and Israel Dagg, and forwards Kieran Read and Sam Whitelock.
Read and Whitelock are expected to re-sign with the union but the three backs are not as clearcut and one or more are expected to head offshore.
Asked if the union has any hope of matching overseas deals, Tew was firm in his answer.
``No, we have always said we never can compete with these clubs if it was just on money. But we ... have got more money from the new collective agreement that we have introduced,'' Tew said.
``We can't match what they can get overseas but what we can do is create a great environment here for the players and there are various initiatives we have worked through that we believe are attractive to the players.
``But the players will make up their mind what is the best deal for them and their families.
``They all know we love them to death and we'd love them to stay, but they've got to make their own decision.''
Tew said the deals for the current players would expire after the tour by the British and Irish Lions next year.
There was no deadline for players to come up with a decision and Tew said the union's door was always open.
The union last week announced a new three-year collective agreement with players in which the payment pool was lifted from $121million to $191million. It also boosted money for individual All Blacks by 50%.
Tew said some of that money was already being used to retain players.
He said obviously the union would love to retain all the players but every case was different.
There was the possibility of sabbaticals for players, and that was just one of the initiatives used by the union to keep players in the country.
Smith (30), who is on leave, is believed to be weighing up a monster deal from French club Pau.
Pau, which sits 11th in the French Top 14 league, already has All Blacks backs Tom Taylor, Colin Slade and Conrad Smith on its books.
Former Highlanders props Jamie Mackintosh and Chris King are also in the side which is into its second season back in the top league after being in the second tier for nine years.
