Productivity in Britain, a key weak point of the country's economy, improved slightly in the July-September period of last year, according to official data published on Wednesday.

After contracting in the previous four quarters, output per hour worked rose by 0.1% in the third quarter compared with the same period of 2018, the Office for National Statistics said.

Growth in productivity is key to the long-term prospects for growth and prosperity of an economy.

"Although productivity grew on the year, the underlying picture is of sustained weakness since 2008, with growth over the past year being only a third of the average over the last 10 years or so," ONS statistician Katherine Kent said.

Over the last decade, annual growth in productivity has yet to even touch its pre-financial crisis average between 1972 and 2008.