Slovnaft will launch regular maintenance of its technology on Friday, investing €67m. It says the maintenance, during which oil processing falls considerably, has nothing to do with the current stoppage of oil transit via the Druzhba pipeline. It has enough oil in its tanks to last three months. Some analysts say Russia put 0.7m tons of polluted crude oil into the Druzhba pipeline deliberately to punish and weaken Belarus and Ukraine. Both are trying to wean themselves off Russian support but still depend on Russian oil. Russia recently tightened conditions for exporting crude oil and fuel to Ukraine.