Russia's ambassador to Warsaw said on Thursday that Poland had blocked the embassy's bank accounts for allegedly financing "terrorist activity", RIA news agency reported.

Russia sent tens of thousands of troops into Ukraine on Feb. 24 in what it called a special operation to degrade its southern neighbour's military capabilities and root out people it called dangerous nationalists.

Ukrainian forces have mounted stiff resistance and the West has imposed sweeping sanctions on Russia in an effort to force it to withdraw its forces.

(Reporting by Reuters; Editing by Alison Williams)