Welsh Government sources tell me they're having to 'reappraise' the way officials work with Whitehall civil servants because of concerns that the neutral civil service is becoming dragged into political attacks on the performance of the NHS here in Wales.
I've been shown the text of an email from a senior official in the UK Department of Health to Welsh Government officials in Cardiff. It's a briefing paper for the Prime Minister for his weekly question session in the House of Commons and lists the now-familiar criticisms of the Welsh health service that David Cameron makes as part of his regular attacks on Labour opponents.
The email is headed: 'Prime Minister's Questions briefing: NHS in Labour-run Wales' and continues 'Confirming that you are content with the briefing that's provided for Prime Minister's Questions on Welsh performance, the most recent of which follows.'
A spokeswoman said nobody at the Department of Health would be commenting. A Welsh Government source tells me it's inappropriate for a senior civil servant to be involved in such an obviously political move. There's a certain amount of wry amusement, too, that officials should be asked to check that the criticism about to be directed at them is correct. The source said,
The source went on to say that the email and two other recent cases could risk the working relationships between top officials in both governments.
That reference to the Surgeon General follows claims in Sunday newspapers that the Armed Forces' most senior medical officer wants injured soldiers to be treated in England because of long waiting times in Wales. I'm told that the comments come from the minutes of a private meeting with the Surgeon General. I'm also told that the minutes hadn't been signed off by Welsh Government officials and wouldn't have been signed off because they were 'inaccurate and misleading.'
Welsh Government sources also question the way that information was released in a Freedom of Information request which, unusually, was released on the same day that it was requested by Conservative MP Alun Cairns.
Senior Welsh Labour figures say this and the Prime Minister's briefing paper are evidence that the Conservatives are waging a political 'war on Wales' masked as concern about the performance of the Welsh NHS. The other view is of course that the attacks are part of legitimate scrutiny of the politicians in charge of a service that's struggling.
Whether or not it's a war on Wales or a war on Welsh Labour, it's a conflict that shows no sign of easing. I'm told that Labour's opponents intend to open a new front in the coming weeks, by focussing their attacks on education standards here.