our political correspondent, chris mason, has more. usually vibrant, bustling, dynamic, and yet for much of the last six months many of our city centres have looked like this. it's time for that to change, says the government. the head of the civil service, sir mark sedwill, says the prime minister believes... this is whitehall, home to loads of government departments. it's actually relatively busy here today but still pretty quiet on weekdays. the government wants four in five civil servants in england to be back at their desks for at least some of the week by the end of this month with more and more people worrying that unless public and private sector workers return to the office there could be huge economic consequences. if we don't see workers coming back until the new year, and workers are a big driver of footfall in city centres, particularly on a monday to friday, then we might see