AMEC has officially split the company internally into an energy and process division and a UK infrastructure and construction arm.
Two separate management teams have been set up to run the different businesses ahead of a proposed sell-off of the infrastructure side in September.
Both teams will present their business plans to the main Amec board by the end of August.
An Amec source said: 'The businesses have been formally separated under the different management teams and this could lead to a demerger of the UK infrastructure business.
'The infrastructure team will finalise its business plan in the next few months before it is presented to the main board, which will make a decision about its future.' The move is the latest stage in Amec's demerger plans following the £707 million sale of French engineering arm Amec Spie to private equity investor PAI last week.
Four European contracting giants were in the hunt for Spie but PAI beat them to the pr ize.
Amec's UK managing director Mike Straughen is overseeing the restructure and John Early heads the UK infrastructure team as chairman.
Under him will be John Moss, who will lead design and project services, and Graham Ludlow, at building facilities services.
The infrastructure arm will focus on three main areas ? investment, construction design and delivery and building/facilities management.
Last year the business turned over £1.2 billion with profits of £21.4 million.
The energy and process division will be headed by chief executive Sir Peter Mason and will also concentrate on three divisions ? energy and mining, power and process and environmental consulting.
One analyst said: 'It looks like it will be an interesting few months at Amec but the smart money has to be on a sell-off of the infrastructure and construction arm.
'It has been moving away from that sector for some time and it would leave the board with the energy and process side to concentrate on, which is sure to offer a lot of future opportunities including the UK nuclear market.'