LONDON, Dec. 4 (Xinhua) -- The British construction sector grew more than expected in November, but Brexit uncertainties are holding back firms from committing to starting building projects, a new survey revealed on Tuesday.

Construction activity improved to a four-month high in November and was at the second highest level since June 2017, according to the IHS Markit/CIPS Purchasing Managers' Index (PMI), led by more house building.

Activity hit 53.4 in November on the scale (above 50 is growth) up slightly from October, and civil engineering and commercial sectors also performed well, with confidence strengthening and employment rising strongly and new orders growth picking up.

But the growth in new orders was limited and the survey showed headwinds hampering growth.

"New orders growth improved from the five-month low seen in October, although it was still at the second lowest level since May and significantly below the long-term average," said Dr Howard Archer, chief economic adviser with EY ITEM Club, a London-based economic forecasting group.

"Some companies' willingness to commit to major new projects at this stage is being limited by Brexit uncertainties and concerns over the economy," Archer added.

"Similarly, confidence among construction companies improved in November but again was still clearly below long-term norms, Brexit-related concerns were reported to be the main factor weighing on confidence."