But the project is now mired in controversy after the Russian environmental watchdog ordered a halt to work under way within a mile of Lake Baikal, the world's oldest and deepest lake and a UNESCO World Heritage site. Oleg Mitvol, deputy head of the Natural Resources Ministry's Environmental Oversight Agency, said: "We have environmental legislation and we will demand that it is obeyed. There should be a pipeline, but it should not spoil the world heritage of Lake Baikal." The ministry also said that a planned oil terminal could threaten Russia's only marine reserve and its oldest nature reserve, which is home to the Amur leopard, arguably the world's rarest big cat. In December the government approved the plan to build a pipeline from Tayshet, in western Siberia, to Perevoznaya Bay, by the Sea of Japan, to service Asian markets during the next decade. Construction was due to start this summer and the first section, from Taishet to Skovorodino, near the Chinese border, was to be ready by 2008.