Trigger play, pause and other Cesium.AnimationViewModel commands from js

For example: I want Cesium.Viewer being paused after initialization.
Currently I write something like:

var viewer = new Cesium.Viewer(‘cesiumContainer’);
viewer.animation.viewModel._pauseViewModel._command();

It works (http://jsfiddle.net/kasheftin/bfW9b/1/).
Is there any other legal method to pause player from js without triggering private methods?

Clock.shouldAnimate = false;

Thank You, this works.