George Osborne is expected to see through the privatisation of the Green Investment Bank (GIB) within weeks.
The move, which is part of strategy to slash public debt, could include selling off 75% of the £3billion venture.
The bank was set-up in 2012 to underwrite low-carbon projects, including windfarms.
Osborne revealed his plans for the sale earlier this year.
The deal was originally due to take place next year. However, sources referenced by the Sunday times have said the auction could be pushed ahead as early as next month.
It would make the deal one of the fastest privatisations on record. It could also prove to be one of the most lucrative, pulling in more than the £2billion sale of the Royal Mail in 2013.