NORTH Melbourne has upped the ante in its bid to retain Daniel Wells submitting an improved offer that could see the star midfielder earn up to $1.1 million over the next two seasons.

North has been in negotiations with the unrestricted free agent for several months, but has been unable to secure his signature ahead of the finals.

Industry sources told AFL.com.au the Roos had a performance-based one-year contract on the table for Wells with a trigger clause for a second year, but it has since emerged the Roos recently submitted a new offer to Wells.

Under this latest deal, Wells would get an unconditional two-year extension and the ability to earn up to $550,000 a season.

If the two-time best and fairest winner's fitness and form hold up over 2017 and 2018, his annual salary will remain close to what he has earned under his existing three-year deal with North.

The parties' negotiations are unlikely to be finalised until after North's finals campaign concludes, but the Roos are believed to be hopeful Wells will continue his career at Arden Street.

As an unrestricted free agent, Wells is free to join a rival club knowing North cannot match its offer. There will be keen interest in the West Australian if his talks with the Roos continue to drag on, but a firm suitor has yet to emerge.

The Kangaroos' increased offer reflects Wells' importance to the club.

With Brent Harvey's looming departure, the 31-year-old is far and away the Roos' most damaging midfielder in open space with his speed and class, while his ability to win his own ball at stoppages remains underrated.

After being sidelined by injury for all bar two games in 2014 and 2015, Wells has made a strong return this season.

Averaging 23 possessions across 18 games, he also led North in goal assists during the home and away season and was fourth at the club for contested possessions, clearances, inside 50s and tackles.