Usage example with a context:
“Every one of these sentences is, to put it mildly, a stretch,” explained one seasoned Kremlin-watcher, and the news this week from Ukraine has been grim, contra Obama’s hopeful pose. While Russia’s economy remains seriously hurt from sanctions and, even more, the sharp drop in oil prices, the notion that this is taming Putin’s baser urges is not only untrue, it’s more likely the opposite of the truth, as I cautioned a month ago.
Is that a preposition? Something similar to the preposition contrary to? I've never seen this one before plus many English dictionaries out there don't even have it listed as a preposition.