I want to know the answer to the following question:
What did most Western countries view as an illegal claim by the USSR?
All the background I'm provided with is that "In the initial period of 1987–1989, this was partially for more economic independence, but as the Soviet Union weakened and it became increasingly obvious that nothing short of full independence would do, Estonia began a course towards self-determination.". Is that enough to answer the question?
Answer: no