The U.K. was much less productive than the rest of the G7 in 2014, lagging by the most since 1991, official figures have shown.
The Office for National Statistics (ONS) said output per hour was 20 percentage points below the G7 average.
The U.K. was behind the US, Germany and France by a large margin and was slightly worse than Italy and Canada.
Productivity is seen as key to helping increase living standards in the U.K. by many experts.
“These figures show U.K. productivity continues to lag behind other developed economies,” ONS chief economist Joe Grice said.
“Since the economic downturn, productivity growth has slowed in most developed economies, but by more in the U.K. than the average.”
The Chancellor, George Osborne, pledged in July to take steps to encourage more long-term investment in infrastructure and by businesses to boost productivity.