 The arguments are likely to heat up. Last week, judges ruled that the ban on lithium mining was unconstitutional. That clears the way for Rio Tinto to resume work. Both the company and the government insist the mine will contribute to both Serbia's economy and Europe's energy security. But they've yet to convince environmentalists of the key issue, whether extracting the mineral crucial to sustainable transport can be done in an environmentally friendly fashion. Guy Delaunay, DW, Belgrade.