In a fresh sign that U.K.'s economy is struggling to return to growth, official data out Tuesday show factory output falling by 0.7 percent in April.

The Office for National Statistics said Tuesday that the broader index of industrial production, including mining, energy supply and water management, was unchanged from March.

The agency said the biggest drag on factory output was in food, drink and tobacco, which were down 5.7 percent year-on-year. The biggest growth area was transport equipment with an 8.8 percent rise in production.

Economist Samuel Tombs at Capital Economics says that given the problems in the euro area, the U.K.'s biggest export market, the industrial sector is likely to drag on growth "for some time to come."

Britain is in recession, with two quarters of shrinking output.