Presumably nobody thought to tell him about this new invention that's been increasing in popularity in recent years called the mobile phone which lets people talk to you wherever you are. Even in the Netherlands.
Meanwhile, he's shown everyone how he's totally not worried by UKIP at all and especially not that rotter Nigel Farage by telling House Magazine that he doesn't want Farage in a leaders' debate if they hold another one before the next general election.
With Cast Iron Dave™ running scared of an EU referendum and a televised debate with Nigel Farage, anyone would think he was turning yellow ...