In mid-March 1920, Žukauskas requested a vacation. Poland launched an offensive towards Kyiv where his family members still resided waiting for an opportune time to return to Lithuania. While waiting for Poland to capture the city, he stayed in Vilnius where he met with Jurgis Aukštuolaitis, one of the organizers of the Polish coup d'état in August 1919, and published an article in the bilingual newspaper "Suvienytoji Lietuva / Zjednoczona Litwa" advocating for a union between Lithuania and Poland. This stirred a controversy among Lithuanian soldiers and deepened their suspicions that Žukauskas was a Polish sympathizer. He took his family from Kyiv but did not return to Lithuania; he stayed in Vilnius and asked to retire from the Lithuanian Army. President Smetona accepted his request on 14 June 1920. There were rumors that he was offered a high-ranking post in the Polish Army. Reportedly, he attempted to organise Polish resistance against the approaching Bolsheviks in Vilnius. He supposedly was trying to take over the command of city's defence, which led to disagreements with Polish officers already in place. He went back to Kaunas on 12 July, two days before the fall of the city, and the day of the signing of the peace treaty between Lithuania and Soviet Russia.