"British ambassador resigns from European negotiations"
He was due to be part of them - I didn't say they'd begun"

In that case Carroll learn to state what you actually mean.

If you state that so-and-so resigns from whatever negotiations it DOES MEAN exactly that - i.e. that negotiations are currently in progress.

If you state that so-and-so resigns his position prior to the commencement of negotiations then negotiations have clearly not started.

we are not mind readers and can only respond to what you write in your usual slapdash approach accompanied by your usual total lack of attention to detail.