Google's European boss took to the stage at Advertising Week Europe just as the storm over adverts appearing next to extremist videos on YouTube hit new heights.

The fact that that Marks & Spencer has joined the government and a clutch of other organisations in withdrawing their ads from Google's platforms means the search giant is facing a crisis of confidence in its ability to police its service.

As Google is effectively the world's most lucrative ad business, losing the trust of its customers is a serious matter. So Mr Brittin started by saying sorry: "We apologise when anything like that happens, we don't want it to happen and we take responsibility."