In the Soviet Union Liebknecht was entrusted, over the years, with senior positions in respect of various government construction projects. Initially, during 1931/32, he worked for an international team around the city planner Ernst May. May had been heavily influenced by what is known in England as the Garden city movement, and in 1930 he had moved with virtually his entire "New Frankfurt" team from Frankfurt am Main to Moscow in order to support the Soviet Union's urban modernisation programme under the direction of powerful "building policy" committees of the ruling Communist Party. Liebknecht was assigned to the so-called "Second May Group" under the leadership of another expatriate German architect, : construction activity was focused on Moscow. Within the "Second May Group" Liebknecht was placed in charge of the "Hospitals Building Sub-group". Alongside these assignments he teamed up with his Dutch colleague Marinus Gewin to enter a submission for an international competition held in 1931 involving plans (much touted but never implemented) for a Palace of the Soviets on the site of the demolished Cathedral of Christ the Saviour near the Moscow Kremlin. By 1932, with some of the initial impetus from Ernst May's group projects, beginning to fade, Liebknecht switched to the "People's Commissariat for Health's Commission for Project Standards" ("Kommission für Projektierungsnormative des Volkskommissariats für Gesundheitswesen "). Then, starting in 1933, he worked for the "People's Commissariat for Trasport and Communications" (" Volkskommissariat für Verkehrswesen und Verbindungswesen"), where he was responsible for the planning of clinics, along with residential and office developments in several important cities and towns, including Magnitogorsk and Stalinsk (as Novokuznetsk was known till 1961). He was provided with a comfortable three room apartment just a few hundred meters from his Moscow office.