Amec, the FTSE 100 engineering group, is understood to have teamed-up with US nuclear giant Energy Solutions to bid for the £2.6bn clean-up of Dounreay power station in the Scottish Highlands.
An announcement confirming the tie-up is expected in the next two weeks, making Amec a strong contender for the so-called "parent body organisation" role. The consortium's main rival is expected to be a venture including US construction group, CHM Hill, and Babcock International-owned UKAEA, of which Amec had been a member until it was forced out this year. The firms had a one-third stake each in the group, but Babcock tried to reduce Amec's share, which meant executives felt that they had to quit.
The Nuclear Decommissioning Authority will not choose a preferred bidder until 2012. Amec won the £22bn deal to clean up Sellafield two years ago as part of a consortium.
Shares in Amec closed at 865.5p on Friday, up 14.5p on start of day's trading. Babcock stock rose 12.5p to 599p.
Amec declined to comment.