Vytautas himself had other intentions: though he accepted the title, he continued to demand Lithuania's complete separation from Poland. He also pursued an ambitious expansionist policy to the east, hoping to conquer Novgorod and Pskov, and he is known to have styled himself "velikii kniaz" or grand prince, a term borrowed from Kievan Rus'. Vytautas even had himself crowned a king by local nobles in 1398. But in 1399, his forces and those of his ally, Khan Tokhtamysh of the White Horde, were crushed by the Timurids at the Battle of the Vorskla River. The defeat left him with no choice but to submit to Władysław’s overlordship once more.