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A family $\mathcal N$ of closed subsets of a topological space $X$ is calleda {\em closed $k$-network} if for each open set $U\subset X$ and a compactsubset $K\subset U$ there is a finite subfamily $\mathcal F\subset\mathcal N$with $K\subset\bigcup\F\subset \mathcal N$. A compact space $X$ is called {\emsupercompact} if it admits a closed $k$-network $\mathcal N$ which is {\embinary} in the sense that each linked subfamily $\mathcal L\subset\mathcal N$is centered. A closed $k$-network $\mathcal N$ in a topological group $G$ is{\em invariant} if $xAy\in\mathcal N$ for each $A\in\mathcal N$ and $x,y\in G$.According to a result of Kubi\'s and Turek, each compact (abelian) topologicalgroup admits an (invariant) binary closed $k$-network. In this paper we provethat the compact topological groups $S^3$ and $\SO(3)$ admit no invariantbinary closed $k$-network.

The groups $S^3$ and $SO(3)$ have no invariant binary $k$-network