It's just Howe's last word.
Coupled with my adding info from Return to Ostagar, where a well meaning Cailan was talking to Orlesians. In addition to Eleanor admitting that her and Bryce just came back from Orlais. Something Nathaniel might've said too. Things just add up in a way where I can see how Howe and Loghain interpreted it all badly. Not that I'm excusing them though. Just sounds like one of those situations where information gets distorted down the grapevine. I think the writers did a good job of presenting a intertwining story of political intrigue here.. it has more depth than the simple interpretation that "Howe = Conniving Weasel Villain". Although he was that as well.
And again I go back to my thoughts on Cailan and Couslands talking with Orlais could have turned out very well. Everyone assumes Orlais was going to try to take Ferelden again, but this is really only based on speculation and what happened in the past. But a generation has gone by. Look as the US and Russia. We went on to have generally amicable dealings. Best of terms? Hard to tell but not at war by any standards. Once lines of communication are opened... things change. This can be said for other countries in Europe that were once at great odds with each other. Times change. People change. Only people like Loghain who carried it so deeply would harbor a grudge and paranoia so strongly. In his case, it is understandable give that he saw it all first hand and led Ferelden to victory but it made him a man capable of seeing them only as an enemy. People think that them sending more troops was proof, but my thoughts are different.
Say you are in some kind of peaceful negotiations with a country you occupied brutually for nearly a century but have not been in for a generation or more. They are facing a blight which will become your blight if it is not stopped. What is you best course of action? Send all the troop you can muster to help save the land you are aiming to have good relations with in the future while also helping ensure that you are solidifying a strong sense of trust in you for helping said country while also saving your lands from a blight by stopping it while it is in their country. There is no downside to that. Only a suspicious person would see it as they were going to occupy us, but logically, WHY would they even try to occupy a blighted land? Sure, it's weakened from the blight but it is also so horribly damaged (takes a decade to recover) that it would actually cost more to take it over because now you are responsible to help it rebuild. Nobody tries to take over crappy third world countries, do they? Of course not, because they are not viewed as having anything to offer which is how it is after a blight and once the blight starts, you've already lost a portion of the land making it far less valuable. It's a wasteland. You are taking over a wasteland, and to what end? So that you can spend valuable resources on it for a decade to rebuild it? The only way that seems like a good plan is if there was something particularly of value in that land that down the line you could call your own. Otherwise, strategically, it does nothing for you.
Also, in the end, nobody was sent which shows they really weren't aiming to take over or they would have showed up when ferelden was at its weakest. This to me says that they were likely aiming at peaceful negotiations and becoming strong allies but with the king and couslands dead, the two that were working hard at forging this alliance, that option no longer appears to be a good one and now after loghains rants about Orlais they are seen confrontationally bringing up old grudges. Hence why alistair tells you things aren't going so well with them in game two.