When the passports scandal first broke, Mr Prosor was invited to the Foreign Office - and emerged, all smiles. The Brits sent investigators to Israel interview the British nationals whose identities were allegedly stolen - but this was widely assumed to be a formality (and perhaps a fun perk for the investigators). That seemed to be the end of the affair, from the British point of view.
The question is, then, why this drastic British action now - weeks after the scandal seemed to have blown over? Miliband could have made his anti-Israeli statement at any point and would have chosen his moment carefully. What is the significance of the timing?
One strong possibility is that the British move is connected to the mammoth row between the Israelis and Americans over building in east (actually, northeast) Jerusalem last week. Political observers will want to know: Have the Americans asked their British counterparts to apply pressure on the Israelis - to squeeze Bibi just a little more, to make it a bit harder for him to resist the Americans' demands? (Even if it turns out this was not the intention, it will surely be the result).
It also seems extraordinary for Mr Miliband to address parliament on this issue at the very moment - 15.30 - when he was due to be the guest of honour at the Israeli embassy's housewarming party. When it was first announced that he would be attending the reception - a week after the Dubai passport scandal erupted - it was interpreted as a strong sign that the Brits wanted to keep things friendly with the Israelis. For Miliband to withdraw, now, in order to issue a strong statement against Israel instead, cannot be a coincidence; what a slap in the face.