Fully indecomposable matrix is primitive

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A non negative matrix $A\in\mathbb{R}^n$ is said fully indecomposable if it doesn't exist permutation matrices $P,Q$ such that $$PAQ=\begin{bmatrix}X &0\\Y & Z\end{bmatrix}$$ where $X,Z$ are square matrices.

A non negative matrix is said primitive if there exists an integer $m>0$ such that $A^m$ all entries strictly positive.

I would like to prove that if $A$ is fully indecomposable then is primitive. I know that

  • if a matrix is irreducible and has a positive element on the main diagonal then it is primitive;
  • a matrix $A$ is fully indecomposable if and only if it exist a permutation matrix $P$ such that $PA$ is irreducible and its main diagonal is strictly positive;

From the first point I deduce that if $P$ is a permutation matrix and $A$ is irreducible, then A is primitive if and only if $PAP^T$ is primitive since simultaneous permutations of row and columns don't change the main diagonal.

Anyway I am not able to conclude, maybe I miss something. Could you help me?