Look, it's not that I don't want to be a part of this, but I just demilitarized to start with. Secondly, as much as I would love to back YOU up, Swat, Mikoyan has been my ally through the war with Caprica, and you're my trading partner. Lastly, should I turn on Rossiya, he's my neighbor, not smart for me to tick him off, regardless of whose side he chooses.
Nonetheless...
Outraged by Rossiya Imperii's blatant disregard of Avalonia's choice to support the Masona, Avalonia cuts its alliance with Rossiya Imperii until it should desist from aiding the thieves guild. Rossiya has proven an expensive ally, as its over-hasty actions at the Caprican mines suggested long ago.
Avalonian warships return to Masona's western shores and begin bombardment. No effort will be made to single out or to spare Rossiyan troops in the area of bombardment. No offensive upon Rossiya will be made; nonetheless, the segment of the all-enclosing-wall bordering Rossiya is being fortified doubly, and the nation begins to re-militarize. No rest for the weary.