Another Allied commission, led by South African General Louis Botha, proposed an armistice in May that would involve the (West) Ukrainians keeping the Drohobych oil fields and the Poles keeping Lviv. The Ukrainian side agreed to this proposal but it was rejected by the Poles on the grounds that it didn't take into consideration the overall military situation of Poland and the circumstances on the eastern front. The Bolshevik army broke through the UNR forces and was advancing to Podolia and Volhynia. The Poles argued that they need military control over whole Eastern Galicia to secure the Russian front in its southern part and strengthen it by a junction with Romania. The Poles launched an attack soon afterward using a large force equipped by France (Haller's Army), which captured most of the territory of the West Ukrainian People's Republic. Urgent telegrams by the Western allies to halt this offensive were ignored. Czechoslovakia, which had inherited seven oil refineries from prewar Austrian times and which was dependent on its contracts for oil with the Ukrainian government, demanded that the Poles send the Czechoslovaks the oil that had been paid for to the Ukrainian government. The Poles refused, stating that the oil was paid for with ammunition that had been used against Polish soldiers. Although the Czechoslovaks did not retaliate, according to Polish reports the Czechoslovaks considered seizing the oil fields from the Poles and returning them to the Ukrainians who would honor their contracts.