VILNIUS, June 25 (Reuters) - European Union sanctions imposed on Belarus potash have put limits on about 20% of exports of the product transported via Lithuania, its main export route, the head of Lithuanian Railways said on Friday. About 11 million tonnes of Belarus potash crossed the Lithuanian border last year, with about 2.5 million tonnes falling under EU sanctions, Mantas Bartuska told reporters. Lithuania"s Klaipeda port shipped almost 10.7 million tonnes of Belarus potash last year via a terminal 30% owned by Belaruskali.