They're asking for more detail, as there was no detail. The far right press and the crazed Brexiteers have leapt on his comment as if it's unreasonable. It's far from unreasonable, he said it was progress but they needed to hear the detail around some of the salient points, which is a perfectly reasonable request.
I've noticed a real panic amongst the hardline Brexiteers in the last few days, they're desperate to force their will and gain the 'no deal' hard Brexit that for some reason they appear to crave. Personally I think they're cacking themselves that the tide is turning against Brexit and they want to force it through at any cost now, in case democracy rears it's ugly head again in a couple of years time. God forbid eh.....