static_assert and class templates

I have a problem with the static_assert feature. When I instantiate a class template directly, everything works as expected. But when I pass it as a parameter for the different class template, static_assert does not work.

template <int X>
class A{
    static_assert(X == 0, "X != 0");
};

template <class T>
class B{

};

B<A<1>> b;           // Static assert does not work
A<1>    a;           // error: static assertion failed: X != 0