There are high levels of radiation around the fast reactor

The UKAEA will sign an alliance with six companies to carry out specialised work on the fast reactor.

It has not been in use since the late 1970s but still has 9km of cables which need to be removed.

Robots will be used during the project because of the high levels of radiation and the risk of fire posed by chemicals inside the reactor.

The UKAEA said that it will be the most complex engineering and environmental challenge of the decommissioning process so far.

Closure plans

It has described the work as a key phase in the programme to make the entire site safe.

The company expects the operation to cost �30m and create at least 50 jobs.

The UK Government announced plans to gradually close down the Dounreay nuclear plant in 1998.

Ministers took the decision after the UKAEA said there was no commercial reason to keep the plant going.

The huge amount of decommissioning work needed to bring the plant's life to an end means there could be jobs at the site for at least another 100 years.