[4] But in April 1920, from a military standpoint, Polish army needed to strike at the Soviets, to disrupt their plans for an offensive of their own.

Petliura was promised military help in regaining the control of Bolshevik-occupied territories with Kiev, where he would again assume the authority of the Ukrainian People's Republic.

[18] Mykhailo Hrushevsky, the highly respected chairman of the Central Council, also condemned the alliance with Poland and Petliura's claim to have acted on the behalf of the UPR.

The Western Ukrainian political leader, Yevhen Petrushevych, who expressed fierce opposition to the alliance, left for exile in Vienna.

[23] On April 26, in his "Call to the People of Ukraine", Piłsudski assured that "the Polish army would only stay as long as necessary until a legal Ukrainian government took control over its own territory".

[24] Despite this, many Ukrainians were just as anti-Polish as anti-Bolshevik,[6] and resented the Polish advance,[5] which many viewed as just a new variety of occupation[25] considering previous defeat in the Polish-Ukrainian War.

[22] Some scholars stress the effects of Soviet propaganda in encouraging negative Ukrainian sentiment towards the Polish operation and Polish-Ukrainian history in general.

[5] The alliance between Piłsudski and Petliura resulted in 15,000 allied Ukrainian troops supporting Poles at the beginning of the campaign,[27] increasing to 35,000 through recruitment and desertion from the Soviet side during the war.

[27] This number, however, was much smaller than expected, and the late alliance with Poland failed to secure Ukraine's independence, as Petliura did not manage to gather any significant forces to help his Polish allies.

Allegedly, having walked out of the room, he told the Ukrainians waiting there for the results of the Riga Conference: "Gentlemen, I deeply apologize to you".

[30][31] Over the coming years, Poland would provide some aid to Petliura's supporters in an attempt to destabilize Soviet Ukraine (see Prometheism), but it could not change the fact that Polish-Ukrainian relations would continue to steadily worsen over the interwar period.