\documentclass{article}
\usepackage{web}
\margins{0pt}{0pt}{0pt}{0pt}   %% Kein Seitenrand
\screensize{180mm}{250mm}      %% Dimensionen: H\"{o}he, Breite des Dokuments

\parindent0pt

\usepackage{pstricks,pstricks-add}

\definecolor{icelandBlue}{HTML}{0048E0}
\definecolor{icelandRed}{HTML}{FF0F00}

\begin{document}

\thispagestyle{empty}

\begin{pspicture}(0,0)(25,18)
%% Flagge (Verh\"{a}ltnis 25 Breite : 18 H\"{o}he)
%% Breite 7 - 4 - 14 : H\"{o}he 7 - 4 - 7
\psframe[linecolor=icelandBlue,fillstyle=solid,fillcolor=icelandBlue](0,0)(25,18)
\pspolygon[linecolor=white,fillstyle=solid,fillcolor=white](0,7)(7,7)(7,0)(11,0)(11,7)(25,7)(25,11)(11,11)(11,18)(7,18)(7,11)(0,11)
\pspolygon[linecolor=icelandRed,fillstyle=solid,fillcolor=icelandRed](0,8)(8,8)(8,0)(10,0)(10,8)(25,8)(25,10)(10,10)(10,18)(8,18)(8,10)(0,10)
\end{pspicture}
\end{document}
