Well, he's clearly telling their governments this.
Do you mean he is giving the other EU leaders a clear message that they have to do us a better deal on free movement? I don't think so, although I agree the BBC is reporting it as such.
In fact, DC is very clear about the fact that this is not possible. They have said it clearly. He completely accepts that message. He recognises that the UK has to accept that too in order to have the best deal on access to the single market (i.e. continued membership) but at the same time realises the UK is unlikely to accept that, wherein lies the key challenge of post-Brexit negotiations. There was, is, and never will be any wiggle room on that. What has actually been said is not at all how it is being reported. The reporting of it is setting the EU up for more UK public disapproval by acting as though discussions are ongoing when they are not. The EU will subsequently be portrayed as having flounced away from the table, when they have not. In fact, there is no table.