Westminster's corridors are humming. The intelligence community has inserted itself into a growing transatlantic row over Iran. Sources tell me MI6 and GCHQ have privately warned Downing Street that the window for a new nuclear deal is closing. Faster than Number 10 wants to admit.
The problem is timing. The White House is pushing for a quick re-entry. Tehran is dragging its heels. And the UK intelligence assessment is blunt. If the US presses too hard, the talks collapse. If they wait too long, Iran enriches enough uranium to make the deal irrelevant.
This is not a public position. This is the quiet briefing happening in secure rooms. The kind of thing that gets whispered over a pint in the Strangers' Bar.
Number 10 is caught. They need to back Biden. But they also need to be seen as a serious player. The French are already briefing against a rushed deal. The Germans are wobbling. The UK is trying to keep everyone at the table.
Meanwhile, the backbenches are sniffing blood. Labour's left is uneasy. The Tory right is sharpening its knives. A bad deal, or no deal, could reignite the civil war that never really ended after Brexit.
The intelligence assessment is stark. Iran's breakout time is shrinking. The so-called 'snapback' sanctions mechanism is a fading option. The real fear in Whitehall is that the window slams shut. Not with a bang, but with a whimper.
And then what? Military action? The UK has no appetite. Another round of crippling sanctions? The economy can't take it. Diplomacy? The White House and Tehran can't even agree on a date.
My sources tell me the PM's national security adviser is drafting options. They range from a 'thin' deal that does just enough, to a public split with Washington. Neither is palatable.
The game is shifting. Watch for the next leak. It will come from someone who knows this deal is slipping away.
