茲布魯奇河
By concluding an agreement with Piłsudski, Petliura accepted the Polish territorial gains in Western Ukraine and the future Polish–Ukrainian border along the Zbruch River. In exchange, he was promised independence for Ukraine and Polish military assistance in reinstating his government in Kiev. Given the powerful opposition against Piłsudski's eastern policy in war-tired Poland, the negotiations with Petliura were conducted in secrecy and the text of the 21 April agreement remained secret. Poland recognized in it Ukraine's right to parts of the former Polish–Lithuanian Commonwealth (before 1772) east of the Zbruch. A military convention was added on 24 April; it placed Ukrainian units under Polish command.