Solve $\min_{\bf x}\|{\bf Ax}\|$, s.t. $\|{\bf x}\|=1$ and ${\bf Bx}\geq 0$

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I would like to solve a homogeneous least squares problem (i.e. a linear least squares problem where the constants are all zero but where I want to avoid the trivial zero solution). The usual form of these problems:

$\min_{\bf x} \|{\bf Ax}\|$, s.t. $\|{\bf x}\|=1$

can be solved by taking the SVD of ${\bf A}$ and the solution is given by the last column of the matrix ${\bf V}$ from the SVD. However, I am interested in solving a constrained version of this problem, namely:

$\min_{\bf x} \|{\bf Ax}\|$, s.t. $\|{\bf x}\|=1$ and ${\bf Bx}\geq 0$

Is there a closed form solution to this problem?