It may have been a staple of wartime German propaganda.
In 1939, Germany claimed to have been attacked by Poland. A number of concentration-camp prisoners were dressed in Polish uniforms, shot, and left at a border location to 'back up' this fantasy.
Since the war, no such claims were until a few years ago, when Soviet army defector 'Viktor Suvorov' published _ICEBREAKER_. In this book, Suvorov claimed that Stalin viewed Nazi Germany as an 'icebreaker', that would smash up Poland, the western powers, and so on, thus making it easy for the USSR to conquer all Europe later on.
The first stage of this plan was the Molotov-Rebbentrop Pact of 1939, which unleashed Germany against these powers, while gaining the USSR control of eastern Poland and the Baltic states. Poland and France were destroyed as military powers, along with several minor states.
By 1941, Germany had done as much damage to the west as could be expected, and that was when the second stage of the plan was to be carried out - a massive Soviet invasion of Germany, its allies, and its occupied territories, which was expected to sweep all before it, clear to the Atlantic.
However, there is essentially no evidence of any such Soviet masterplan, nor is there any evidence of Soviet planning for a 1941 attack on Germany other than vague outlines.
This last part is the dog that didn't bark. As Sherlock Holmes once remarked, '_That_ was the curious incident.'
Because after 1941, there was absolutely no reason for the USSR to keep such plans secret. If anything, it was in the interest of the USSR to publicize such plans, even if they had to be faked. It was a matter of some considerable embarassment to the USSR that in 1939-1941, the USSR was practically a German ally, and thus an accomplice in Hitler's crimes.
If it could be shown that the USSR's position was only temporary, and that the USSR had definite intentions of 'doing the right thing' (and attacking Nazi Germany was surely 'the right thing'

, that could only make the USSR look better and offset the negative impact of the Molotov-Ribbentrop deal.
This was true at _any_ time after 1941, yet (if Suvorov is to be believed) Soviet authorities not only did not reveal the plans to the world, they kept them utterly secret, even after the fall of the USSR and the opening of Soviet military archives to western scholars.
It just does not make sense.