Consultant Atkins is to join Amec in the race to acquire British Nuclear Group, the decommissioning arm of the government's nuclear body, British Nuclear Fuels.

Atkins has confirmed that it would be interested in bidding for BNG, and said it had an "open mind" on whether to bid for all or part of it. A source said: "We're interested in upskilling our nuclear capacity."

Atkins may also consider joining forces with another nuclear specialist such as Bechtel or Fluor. These engineers may be interested in the other parts of BNG, such as the part that operates the Sellafield nuclear power plant. BNG employs 14,000 people.

Nuclear operator: BNG runs the Sellafield plant

Nuclear operator: BNG runs the Sellafield plant

The government is due to announce by the end of March whether BNG will be sold in full or in part - or at all. Westinghouse, BNFL's nuclear reactor arm, was recently bought by Japanese firm Toshiba, and some sources, including BNG chief executive Lawrie Haynes, see merit in disposing of BNG quickly as well.

BNG's total value is difficult to determine because of uncertainty over which parts will be sold off and the future of its main contracts. Estimates vary between £100m and £500m.

BNG’s total value is difficult to determine. Estimates vary between £100m and £500m

As BNG's contracts will be re-let to the market from 2008, some commentators have argued that the firm's value would be greater if it picked up decommissioning contracts before being sold.

The sale of BNG is also affected by whether the government feels it wants to totally sell off its nuclear assets to foreign firms as the UK looks set to embark on a new nuclear power programme.

One source said: "There's a British nuclear angle here. We've already sold Westinghouse to the Japanese, so the issue is whether you get rid of BNG as well, which would mean getting rid of almost all UK plc's nuclear capability."