The local authority is desperate to see the hugely congested A453 improved.
The scheme was one of 14 road projects put on hold after last autumn’s Comprehensive Spending Review.
Since then the Department for Transport has indicated it would like to identify a small number of ‘reserve’ schemes where construction could potentially start earlier if circumstances allowed.
Nottinghamshire council hope the cash offer will improve its chances of being part of the accelerated programme.
Council Leader Kay Cutts said: “The A453 is the weakest link in the regional road network and the road, in its current state, is severely limiting the economic recovery and development of the area.
“Its widening is fundamental to unlocking the huge economic potential of our vibrant county. We already know that the traffic delays encountered, especially by businesses, are having a detrimental effect upon inward investment.”
The council sent a letter to Transport Secretary Philip Hammond this week detailing its contribution.
Councillor Cutts added: “Nottinghamshire County Council is keen to do everything in its power to expedite this situation. Our contribution would be raised through borrowing and repaid over a number of years because of the challenging budgetary pressures we’re currently facing.
“This is a major financial decision for us and we don’t underestimate the significance of this offer at a time of much-needed capital support for our schools, libraries, youth centres and older people’s facilities.
A decision from the Government as to whether any of the reserve schemes will be accelerated for early construction is expected this year.