The deal will see Serco pick up the unit for £50 million and the sale is part of Carillion’s plan to sell off £300 million of non-core assets by the end of 2018.
Carillion, which has around 43,000 staff worldwide, has been thrown into crisis since a hefty profit warning in July, which sent its shares tumbling by more than 70% in one week.
The group also intends to dispose of its remaining UK healthcare contracts next year.
However, previously announced plans to sell its Canadian businesses are being looked at again.
“While Carillion is continuing to pursue the disposal of the group’s Canadian businesses, it is also evaluating whether a better result for the group would be achieved by retaining for now certain of those businesses,” the firm said in a stock market update.
The infrastructure company also said that it has signed two credit facilities that have helped give it between £170 million and £190 million of “headroom” as Carillon looks to bolster its balance sheet after it said it was struggling to stay within borrowing limits.
Keith Cochrane, interim chief executive, said: “Today we are announcing progress on a number of fronts and whilst our customers and creditors continue to be supportive, much remains to be done.
“We remain focused on executing our disposals and cost savings programmes while continuing our discussions with our lenders and other stakeholders to explore further ways of strengthening Carillion’s balance sheet.”
Earlier this year the firm revealed mammoth half-year losses totalling £1.15 billion, having been dragged down by a series of restructuring charges.