FILE PHOTO: Cranes fill the sky above a construction site in central London, Britain August 21, 2018. REUTERS/Phil Noble

LONDON (Reuters) - Growth in Britain’s construction industry ebbed in January to its weakest since icy weather beset the sector last March, as uncertainty around Brexit dragged particularly on commercial building work, a business survey showed on Monday.

The IHS Markit/CIPS UK Construction Purchasing Managers’ Index (PMI) fell to 50.6 from 52.8 in December, below all forecasts in a Reuters poll of economists that had pointed to a reading of 52.4.

Growth in the housebuilding and civil engineering sectors slowed sharply and activity contracted in the commercial sector for the first time since March, when construction was hit by unusually cold temperatures.

Construction firms hired staff at the slowest pace since July 2016, just after the Brexit referendum, as optimism soured ahead of Britain’s departure from the European Union, scheduled in less than two months’ time.

“Delays to client decision-making on new projects in response to Brexit uncertainty was cited as a key source of anxiety at the start of 2019,” Tim Moore, economist at survey compiler IHS Markit, said.

A similar survey of the manufacturing sector also showed a sharp slowdown underway, caused by a cooling global economy as well as Brexit uncertainty.

Prime Minister Theresa May, under pressure from her own Conservative Party, wants to reopen a Brexit treaty with the European Union to replace a contested Irish border arrangement, something Brussels has rejected.

Investors have urged the government to ensure an orderly exit from the club it joined in 1973.

The closely watched IHS Markit/CIPS survey of services companies, which accounts for the bulk of private-sector activity, is due on Tuesday.