LONDON -- UK new-car sales rose by weak 1.3 percent to 343,255 vehicles in the important sales month of September.
The increase was disappointing compared with other European markets as consumers hold back on purchases due to Brexit uncertainty, industry association SMMT said.
By contrast, France and Germany posted 17 percent and 22 percent growth.
Sales in most EU markets were inflated last month by comparison to a poor month in September 2018 when new WLTP type approval rules depressed demand.
"We expected to see a more significant increase in September, similar to those seen in France, Germany, Italy and Spain," SMMT Chief Executive Mike Hawes said in a statement. "Instead, consumer confidence is being undermined by political and economic uncertainty."
Last month's increase was driven by fleet demand rather than consumers. September is one of two months each year in the UK when license plate series changes typically prompt high demand.
Year-to-date registrations in the UK are down 2.5 percent. The new car market declined by 49,000 cars in the first nine months, the SMMT said.
Electric vehicles, including full electric and plug in hybrids, were the only bright spot.
Battery-driven car sales more than tripled to 7,704 units in September, driven by deliveries of models including the Tesla Model 3 and Nissan Leaf. Plug-in hybrids sales grew a more modest 23 percent, according to data from the group.
In September 2018, UK sales slumped by more than 20 percent as tougher WLTP emissions rules came into force in the European Union, disrupting the availability of certain vehicles and prompting some automakers to offer sales incentives ahead of the change.