An eight-story office block controversially erected on a major Athens junction was illegally built, according to a decision by Greece’s highest administrative court that was made public yesterday. Ruling on a suit by Ambelokipi residents – who wanted the prime site on the corner of Alexandras and Kifissias avenues preserved as an open space – the Council of State said the building’s permit had been illegally issued. The office block was set up by a private developer on the former Thon Estate, which contains a chapel attributed to the celebrated 19th-century architect Ernst Ziller, following a presidential decree in August 2002. A section of the plot was left undeveloped and is now a public area. The Council of State found that, apart from the January 2002 permit, the decree was also illegal, and rescinded both. It is unclear what effect this will have on the building.