Saving TiKz Picture in a Folder in Parent Directory

Question

Is there a simple way to save a picture with the `tikz external library' in a different folder in the parent root.

%File C:/project/tikz/main.tex
\documentclass{article}
   \usetikzlibrary{external}
   \tikzexternalize[prefix = ../figs/]% Should refer to C:/project/figs

\begin{document}
    \begin{center}
      \tikzsetnextfilename{picture1}
      \begin{tikzpicture}
        \draw (0,0) rectangle (4,4);
      \end{tikzpicture}  
    \end{center}
\end{document}

When I used the option tikzexternalize[prefix = ./figs] in the code, tikz created a new folder within the current folder, and didn't navigate as I expected.