By 30 July, the Greek army was outnumbered by the counter-attacking Bulgarian army, which attempted to encircle the Greeks in a Cannae-type battle, by applying pressure on their flanks. The Greek army was exhausted and faced logistical difficulties. The battle was continued for 11 days, between 29 July and 9 August over 20 km of a maze of forests and mountains with no conclusion. The Greek King, seeing that the units he fought were from the Serbian front, tried to convince the Serbs to renew their attack, as the front ahead of them was now thinner, but the Serbs declined. By then, news came of the Romanian advance toward Sofia and its imminent fall. Facing the danger of encirclement, Constantine realized that his army could no longer continue hostilities. Thus, he agreed to Eleftherios Venizelos' proposal and accepted the Bulgarian request for armistice as had been communicated through Romania.