Enterprise, the private equity-backed infrastructure support services firm that is the subject of merger speculation with social housing specialist Connaught, posted flat turnover of £1bn in 2009

The figure fell marginally from £1.09bn to £1.06bn, which the company said was due to reduced business in the telecoms and water sectors. Its operating profit before exceptional items rose slightly from £65.2m to £67.5m. The Lancashire-based company said the outlook was “highly encouraging”.

The firm, which has 170 UK offices and employs 13,000 staff, operates in the maintenance sector in the housing, energy and transport markets. Its clients include the Ministry of Defence, Severn Trent Water, the Highways Agency and Transport for London.

Last week, the share price of Connaught rose 2% amid speculation that Enterprise’s backer, private equity firm 3i, was planning an estimated £600m takeover bid to merge the firm with Enterprise.

Connaught and 3i declined to comment, but a source close to the situation said: “In order to extract some value from its Enterprise investment, 3i would have to do something like combine it with Connaught. Given how the market has dipped since 3i bought Enterprise, the move for Connaught is certainly in their thinking.”