A Belomorsk Naval Base representative told RIA Novosti this morning that the planned third and final Bulava test for 2010 has been postponed until early next summer:
“The freezing White Sea ice interfered with the conduct of testing, which was planned for 17 December from onboard nuclear submarine ‘Yuriy Dolgorukiy’.”
The next test will likely occur in June when the pack ice thaws.
Russian Defense Policy 
It is not understandable that due to ice the Bulava missile testing cannot be conducted. In real situations you do not have any such options as this. On the other hand the U.S. satellite tracking system might be able to detect the submarines under the ice and thus will be able to target them without the fear of retaliation through ice. Could anyone throw some light on it?